PLAIN BASE FIXED UNDER 1" AVERAGE

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biddulph posted this 30 November 2012

Hi Joe, please excuse my ignorance, but what's a 'fixed base' bullet?

I'm having troubles getting that kind of accuracy out of gas checked bullets!

Cheers

James

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RicinYakima posted this 30 November 2012

James, Here in the US we have two types of cast bullet shooting. One is breech seating, where the bullet is forced into the rifled part of the barrel, and a powdered case is put behind it. The other is where the bullet is inserted into the case and looks and acts like “modern” ammo.

HTH, Ric

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Wayne S posted this 30 November 2012

joeb33050 wrote: Wednesday at the range a shooter asked me if shooting plain based bullets in fixed ammunition <1"was a reasonable goal. Aside from a step-necked case in my 30-30 bench gun, I don't think I've ever been able to do it. I'd like to hear from anyone who can average under 1” for five 5 shot 100 yard groups, fixed plain base. Thanks; joe b.What do you mean by “ FIXED PLAIN BASE” ??

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pat i. posted this 01 December 2012

biddulph wrote: Hi Joe, please excuse my ignorance, but what's a 'fixed base' bullet?

I'm having troubles getting that kind of accuracy out of gas checked bullets!

Cheers

James

Your not alone by any means no matter what you read on some of the forums.

"What do you mean by ” FIXED PLAIN BASE” ??"

All loaded up and ready to shoot........not breach seated. I asked a similar question a while ago in my thread about PB bullets in fixed cartridges and didn't get many replies either. One group means nothing to me and shooting at 50 yards means nothing to me. If someone is getting 1 inch or under aggregates at 100 yds with a PB bullet loaded in a fixed cartridge I'd sure like to hear about it also.

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linoww posted this 01 December 2012

Shoot a few wallet groups under 1” yes,average NO.Like Pat says 50 yard screamer groups dont seem to correlate to screamer 100 yard groups with planbase.

George

"if it was easy we'd let women do it" don't tell my wife I said that!

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biddulph posted this 01 December 2012

OK, this raises the next question:

Whats the objective of breech seating? If its jamming the bullet into the lands, isn't that a bit too much of a good thing? I've been of the understanding that 20 thou off the lands was the acid test.

But, Im interested. Primarily because i have a couple of Weatherby's who's long long free bore makes the 20 thou 'rule' impossible to 'enforce'...

Any advice would be great. I've never ever thought of breech seating!

cheers and thanks to all you great guys out there, this forum is full of esoteric info!

james

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.22-10-45 posted this 01 December 2012

Hello, biddulph. Breech-seating has long been the recognized method of starting a lead bullet straight and true into rifling without the variables introduced by the ctg. case. Before B.S., Pope was using muzzle/breechloading..his thinking was the bullet would leave muzzle in same condition it went in..and any fins displaced by rifling would be pushed forward on bullet..leaving base true & burr-free. Modern bench-rest practices can overcome most if not all of these problems..close chambers/throats, turned case necks. Special tapered throats (Ardito)..seating out with only gas check or so in neck. All seeking to do same thing..start the bullet straight. I have always seated my .22 C.F. cast to engrave first band when action closes..As well as most of by bigger bore stuff.

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linoww posted this 01 December 2012

I believe Pope got this system from George Schalk? Memory may be failing me though. An interesting note is that Bev Pinney is using a Muscrave bolt gun with a breech seater in a short 30-30 to .32 case and he tells me it shoots as well as his Miller did.He shot some good groups with it in Spokane when i was there last year.

"if it was easy we'd let women do it" don't tell my wife I said that!

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.22-10-45 posted this 01 December 2012

Yes I believe your right about Schalk..If I remember right..pope's rifling had no sharp corners. Just remembered about work Dr. Mann did with B.S. jacketed..his bullets had a base band..forward was bore-ride. Chamber/throat was machined for this bullet.

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argie1891 posted this 01 December 2012

i wish i could average 1 inch groups not saying i never shoot 1 inch groups but i shoot more over an inch than under. it is much easier to forget all groups except the wallet groups. i think it would be interesting to keep track of say 25 or 50 groups and actually see what was average. argie1891

if you think you have it figured out then you just dont understand

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pat i. posted this 01 December 2012

biddulph wrote: But, Im interested. Primarily because i have a couple of Weatherby's who's long long free bore makes the 20 thou 'rule' impossible to 'enforce'...

james

I've always thought the Weatherby throats would be perfect for cast bullets and still do although I've never had one. Get an LBT mould that casts or is sized a half thousandths under free bore diameter and you're doing what most of the the cast bullet BR shooters are doing. To pick what to order seat a bullet backwards in a case to get the free bore length, add the length of the ogive for the caliber you're shooting which is listed on Veral's website, and add to that about 1/2 or 3/4 of the neck length so the bullet will be in the neck when seated and you should be good to go. Bullet weight doesn't matter as long as everything else fits.

As an example a 300 Weatherby mag has a .360 long free bore. A LBT 30 caliber SP has an ogive length of .340. The 30 Weatherby mag case has a .330 neck length. If you used .275 of that you'd end up ordering a LBT SP bullet .975 (let's just go 1 inch) long which should weigh about 180 grains or so out of WW if you order it with one lube groove. Size the bullet a half thousandths under free bore diameter and seat it a little long so it seats on bolt closing and it might shoot pretty well.

I don't know if the .020 rule applies to cast bullets. I've always had my best luck jamming, or at least kissing if I'm using a real light neck tension, the bullet into the lands.

None of this is by any stretch of the imagination related to the subject at hand but I felt like writing something.

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John Alexander posted this 01 December 2012

Pat,

You obviously need a 300 Weatherby to work with. I think what you describe would be a great thing to try. Mike Mohler won the nationals with a 243 which has at least as much “extra” case as a 300 Weatherby. Plain based bullets out of that big case would be interesting. Subsonic loads even more interesting.

John

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linoww posted this 01 December 2012

John Alexander wrote: Pat,

You obviously need a 300 Weatherby to work with. I think what you describe would be a great thing to try. Mike Mohler won the nationals with a 243 which has at least as much “extra” case as a 300 Weatherby. Plain based bullets out of that big case would be interesting. Subsonic loads even more interesting.

John

Maybe with a case that big the powder gasses would be cool by the time it reached the bullets base<g>

"if it was easy we'd let women do it" don't tell my wife I said that!

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pat i. posted this 01 December 2012

28 grains of Varget. Sill seal wad on top of the powder. LBT gas checked bullet set up like I described with the single groove full of LBT Blue....Result.... Guaranteed seat at the winners table at the 2013 National Championship with George Damron as your personal servant for the evening. :D

On another subject. I just found a bottle of Rooster Jacket I must have bought some time in the distant past and never opened. Does anyone have any experience with it? I'm going try shooting my PB tomorrow using Blue Dot and Unique subsonic loads and while the bullets I'm using are lubed with LBT Blue something like the Rooster might be a better option to try down the road for the slow pokes. I also opened the flash hole on one case with a 9/64 drill. Read somewhere it helps with light loads. Anyone have any first hand experience?

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linoww posted this 01 December 2012

I tried opening flash holes just once and with unique i couldn't see a difference.it was only one set of groups though.It will be interesting to see ho wit does for you.

"if it was easy we'd let women do it" don't tell my wife I said that!

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RicinYakima posted this 01 December 2012

For smokless, the only thing I have tried it on, it helps with loads of too slow of powder or ball powders,at least the ignition and SD's are better. When I was working with surplus ball powders, it made my 30/06 groups go from 3 1/2 inches to 3 inches. With 16.0 grains of A2400, there was no difference I could see, all groups were about 1 5/8” in the Springfield. WFIW, Ric

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John Alexander posted this 01 December 2012

Pat,

You might try a few of the bullets lubed with LBT rolled around in Rooster Jacket. I have sometimes found that a coat of LLA helped a bullet although they had LBT in groove. It doesn't cost much to try.

John

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.22-10-45 posted this 02 December 2012

Hello, joe. Please forgive me for sounding dense..but what exactly is ment by “average” 5 shot group? Does this require 1” or under each and every time rifle is taken to range? Or say in a summers worth of shooting..adding up total dia. of groups & dividing by # of targets? I have never done this before..might proove interesting!

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linoww posted this 02 December 2012

I take this to be more dealing with bolt action/single shot sporters in CBA matches for 5 shot group aggregates (four groups).

"if it was easy we'd let women do it" don't tell my wife I said that!

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Pigslayer posted this 02 December 2012

Joe seems to have made himself unavailable for comment. Hmmmmmmmmmmmmmmmmmmmm.

If someone else had of done to me what I did to myself . . . I'd have killed him. Humility is an asset. Heh - heh.

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joeb33050 posted this 02 December 2012

.22-10-45 wrote: Hello, joe. Please forgive me for sounding dense..but what exactly is ment by “average” 5 shot group? Does this require 1” or under each and every time rifle is taken to range? Or say in a summers worth of shooting..adding up total dia. of groups & dividing by # of targets? I have never done this before..might proove interesting!

That would be the average of five 5 shot 100 yard groups. Just my way of testing accuracy. Thanks; joe b.

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pat i. posted this 02 December 2012

John Alexander wrote: Pat,

You might try a few of the bullets lubed with LBT rolled around in Rooster Jacket. I have sometimes found that a coat of LLA helped a bullet although they had LBT in groove. It doesn't cost much to try.

John

John,

I removed the LBT from 10 bullets and double coated them with the Rooster. I'll shoot them last so that if things go like they usually do for me I won't have to scrub the lead out at the range.

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John Alexander posted this 02 December 2012

I am by nature overly optimistic, but I think we may be seeing some recognition that if you want to say something about accuracy it ought to be based on the average of a “bunch” of groups, not just one group or worse the best group (often three shot) that sometimes still appears in the popular gun magazines.

Shooting Times now usually reports the NRA (and Joe B.) standard of five five shot groups. That is real progress for anyone who wants to know how that new Ruger American they are hyping really did shoot -- at least that sample.

This trend is promising and if we can encourage more shooters to report averages our discussions will mean more. The size of your “wallet” group tells us nothing.

I think the argument over whether groups should be 3,5, or 10 shots is less important than the total number of shot fired. Any will do if you shoot enough shots. Ten 3s, six 5s, or three 10s will each give you a pretty good idea (of course recognizing that a 1” five shot group is approximately equivalent to a .73 three shot group or a 1.25 ten shot group.) Yes there are pros and cons for different number of shots per group but any will give a pretty good idea.

Pat,

Be sure and let us know if Rooster Jacket helped.

John

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pat i. posted this 02 December 2012

John I think the Rooster Jacket did help. Seven shots on the target below. Can't count the sighter when I was adjusting the scope but the one that dropped out has to be counted. Planned on shooting the other three into the group but got so freakin excited I knocked them off the bench.

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pat i. posted this 02 December 2012

Rest of story. I used the case that I opened the flash hole with a 9/64th drill bit and the primer backing out problem is solved. Load was about 9.2 grains of BlueDot with a Fed LR magnum primer. I put a little taper on the front of my bullet and continue to use the P-Wads. The first group I shot today had one groove full of LBT Blue and they went all over the place. I started removing the lube completely leaving only what was left on the bands from lubing in an oversized H&I die and things improved. The groups below aren't great but there seems to be a lot more little clusters in the pack and I think if I find a way to make the BlueDot meter a little better I might have a winner. I'll cast some more up and try it again with just the Rooster after hunting season.

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madsenshooter posted this 02 December 2012

Blue Dot metering in the el-junko Lee Perfect powder measure. Handle up, tap, tap, tap, the top of the hopper. Handle down to dump the load. Reasonably consistent, provided you don't forget a tap or two.

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Ken Campbell Iowa posted this 02 December 2012

john a. sez: I think we may be seeing some recognition that if you want to say something about accuracy it ought to be based on the average of a “bunch” of groups, not just one group

ken sez: i have been thinking that maybe we could also stop calling those wider shots on the target .. not ” outliers ” but simply ” liers ” ...seems more fitting somehow, not sure why ..

btw, how about we all make a new years's resolution to start shooting 1.2 moa groups ? i shot 2 to 4 moa with 80 year old rifles when i wuz a kid, not knowing all this good info we have created up to date.

hey, wait a minute .. i am STILL shooting 2 to 4 moa .. what the ...

sigh ken

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muley posted this 03 December 2012

Pat, are you sorting cases or just loading and shooting them as they come along?

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pat i. posted this 03 December 2012

Only using 1 case.

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CB posted this 03 December 2012

I saw an experiment once a couple of guys built a plain base rail gun that shot fixed ammo and I have seen it shoot and groups (5 shot) were well under 1". It was a 30 BR and they used a Lyman 310299 with the gas check shank turned out of the mould. They were using H-322 powder loading a single case. No crimp on the bullet and the throat was tapered. I am sure that the bullets were tapered also. None the less they used a PVC wad and pounded them down there.

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argie1891 posted this 03 December 2012

the nice thing about old age is i cant remember any groups over 1 inch. damn maybe old age aint that bad afterall. arige1991

if you think you have it figured out then you just dont understand

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CB posted this 03 December 2012

I like the way you think!

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John Alexander posted this 03 December 2012

My Lee meters Blue Dot better than my Redfield but still not good. I will try Madsenshooter's method.

Pat, The Rooster group looks promising. I have also sometimes found that less lube is better. Even trying one coat of Rooster might be worth doing. John

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joeb33050 posted this 04 December 2012

I asked the question on the ASSRA forum and got several mentions of Merrill Martin. What I remember of his work was about “ldpe” wads. I have used .30 cal plastic wads for years, never helped accuracy but did stop any leading-all with pb bullets. What have I forgotten about him/his work?

Another subject: Is there a gunsmith who will taper-throat a Savage barrel? I'm thinking about a new 300AAC barrel to work on pb subsonic loads. Thanks; joe b.

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nimrod posted this 17 December 2012

I was able to get to the rifle range today and shoot some groups for my first attempt for a five shot five group agg for under one inch. It was a bit more windy that I would have liked but it turned out OK. the five groups measured 1.073 .763 .823 .855 .988 for a average of .9004.

I was shooting a 38-55 fixed ammo using a accurate Molds 38-285D cast 20/1 14.8 grains of IMR 4227 Rem 2 1/2 primer Alberta Schuetzen lube CPA action with a Badger barrel with a 15 inch twist. .060 LDPE wad seated under the bullet

I do have pictures if I can figure out how to get them on here.

Richard

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joeb33050 posted this 18 December 2012

nimrod wrote: I was able to get to the rifle range today and shoot some groups for my first attempt for a five shot five group agg for under one inch. It was a bit more windy that I would have liked but it turned out OK. the five groups measured 1.073 .763 .823 .855 .988 for a average of .9004.

I was shooting a 38-55 fixed ammo using a accurate Molds 38-285D cast 20/1 14.8 grains of IMR 4227 Rem 2 1/2 primer Alberta Schuetzen lube CPA action with a Badger barrel with a 15 inch twist.

I do have pictures if I can figure out how tio get them on here.

Richard

Thanks, Richard. This is the first example. I'll keep records. Please repeat the test and let us know what happens. I'm hoping that this leads to a solution. I've loaded 314299 WLP .3095” 2.300” no gc, lyman super moly Unique, 9.0, 9.5, 10.0 for a try. t would help if folks reported what DIDN"T work. joe b.

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joeb33050 posted this 20 December 2012

Shooting Fixed, plain-base bullets 12/19/12 Savage 10, .308 Win., Simmons 6.5-24X, 100 yards

314299, .3095", 3.000", Lyman Super Moly, bottom grease groove + gc recess lubed

15/A#9, .060” plastic wad, 8 shots, 2.1", no lead-this is good GC load-does plastic wad keep lead away?-yes

9.0/Unique 1.6", 1.85", 1.325", 1.525” Avg. 1.575"

9.5/Unique, 1.2", 2.35", 2.3” Avg. 1.950"

10.0/Unique, 1.875", 1.5", 1.5” Avg. 1.688"

See the clear outliers on 5 of 6 groups in the picture of the target, 9.5 and 10.0 grains of Unique. This is typical, and why I can't make plain based fixed shoot well.

No lead. The above followed by 15/A#9, 31141 .312", 2.740", groups 1.4", 1.2", .725", 1.325", .975” Avg. 1.125” so there was no lead.

The third patch through the bore was clean.

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nimrod posted this 20 December 2012

Joe you didn't say what alloy the bullet is? It's my feeling that a softer bullet of about 20/1 is probably more accurate in this application. Along with a softer lube something as simple as Emmerts or possibly NRA 50/50. I think that a powder similiar to AA# 9 is going in the right direction possibly dropping the charge down some might help also pistol primers have been known to help.

It might be a while before I get back to the range this morning we have 28 degrees and dropping fast, 48 mph wind gusts, and blowing and drifting snow.

Richard

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John Alexander posted this 20 December 2012

"we have 28 degrees and dropping fast, 48 mph wind gusts, and blowing and drifting snow."

Ah yes, fond memories of Basic at Ft. Leonard Wood, MO fifty five years ago. Sorry for the digression.

I promise to try some plain base fixed 22s to make up for my sin.

John

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joeb33050 posted this 20 December 2012

It's much too hot to cast outside here, too hot to sit in the sun. However, the pool is very comfortable. I once lived in a cold area. Still asking WHY??? Nyah nyah. joe b.

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R. Dupraz posted this 21 December 2012

Yep, there's snow in the driveway the temp is near 0 and the pool, if we had one, would be frozen over. But, know why I stay? the real reason? It keeps the riff raff out!

RD

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joeb33050 posted this 22 December 2012

Back when I was proving beyond a shadow of a doubt that I couldn't shoot offhand, I fired about 1.32 zillion cast bullets out of 30/06 etc. .30 rifles with 10-12/Unique. This load will shoot 10/4” 200 yards very reliably. Unique has never been the most accurate powder for me, but has unfailingly been a “pretty accurate” choice. So, I'm starting with Unique to get a base line. I cast with a mix of alloy with a lot of WW and some other stuff. I make a big batch, then it's all the same. Monitor with bullet weight, currently 314299 is ~202.5 gr., fairly soft. I use LP primers for almost all CB loads, not that 've ever been able to prove increased accuracy-but because L. Hall told me to. I've converted to Lyman Super Moly because the guns clean in few, ?3?, patches.3rd patch is frequently clean. I won't negotiate on this. I'll load this weekend and shoot Wed., as long as its not too hot. Thanks; joe b.

nimrod wrote: Joe you didn't say what alloy the bullet is? It's my feeling that a softer bullet of about 20/1 is probably more accurate in this application. Along with a softer lube something as simple as Emmerts or possibly NRA 50/50. I think that a powder similiar to AA# 9 is going in the right direction possibly dropping the charge down some might help also pistol primers have been known to help.

It might be a while before I get back to the range this morning we have 28 degrees and dropping fast, 48 mph wind gusts, and blowing and drifting snow.

Richard

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John Alexander posted this 27 January 2013

Yesterday I shot a few plain based bullets in a rifle. This was the first time since I used gas checks over fifty years ago and found that groups shrunk amazingly. (I have used PB in pistols with good results of course.)

I used the same 85grain bullet I have been using in competition because I knew it fit fairly well, the same lube and amount plus .060” thick PVC wads. I used a Savage 223 low profile M-12 which shoots the bullets well with gas checks.

I shot them at 1,350 with 5 grains of Blue Dot. The report on my results is short. Accuracy went from poor to terrible in six shots and the first patch pushed out sheets of lead which came out easily. I will check bullet fit and add powdered mica next time. Any advice you can offer would be appreciated.

Pat, it looks like you may have set the standard too high for my efforts.

John

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nimrod posted this 27 January 2013

John I think that if you rolled those bullets in some Alox or 45-45-10 they might shoot better. Then if that's not good enough mix up some Emmerts and apply that to the lube grooves. For some reason these plain base loads do better for me if I use a softer lube and softer bullet that what is used for gas checks.

And I really think that for a plain base bullet to work well it needs a mold cut for that exact purpose. Just dropping the gas check off an existing mold ain't gonna work very well, you might get a good group now and then but for consistant accuracy then this needs to be taken very seriously.

A throat cut for the purpose intended a properly designed bullet mold cut to fit the throat perfectly along with the proper lube and some very carefull reloading would probably get much better results. To expect a factory chamber and existing mold sans gas check to achieve the goals stated is going to be very difficult to make work.

This has been discussed over on the ASSRA boad a while back and these people shoot plain base bullets very well. Most of them think that it is next to impossible to do with fixed ammo, but they are somewhat biased to breech seating and it does work every well. There has been a few people do it on a consistant bases and I think that it can be done but it's going to take some serious effort namely time and money.

Richard

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pat i. posted this 27 January 2013

I don't know what gives with shooting PB bullets in a fixed cartridge but I'm not giving up. I'm starting to think lube is going to be the big issue. Maybe without the scraping effect of a gas check lube fouling is causing issues. But that's just conjecture at this point. I also think a PB bullet in a fixed case isn't going to be able to match the speeds attained by breach seating so subsonic is going to have be he way to go, Again just conjecture at this point. I have no serious opinions formed one way or the other. It doesn't look like many people shoot PB bullets in bottle necked cartridges so this is an area open to a lot of trial and error. With the cost of components always on the rise and aging shoulders it does have the upside of mild recoil and low cost so maybe more people will eventually give it a go and we can figure something out.

Once the weather breaks I'm going to try out that floor milk stuff I bought. If that doesn't work I'll look around for other wax coatings that look like they might work. I tried LBT Blue and Emmert's loaded in the lube grooves and they were about the same. 45-45-10 was a little better but not much. Only shot that one group with Rooster Jacket but it showed promise. I'm not one to shoot when it's 20 degrees out so further tests will have to wait til the spring.

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John Alexander posted this 27 January 2013

Richard,

Thanks for your thoughtful answer.

The bullets fired had a lube groove of LBT blue and two coats of LLA. I was hoping that would help seal things up. I will try a softer lube in the groove and a softer bullet as well

I understand your recommendation for a special throat and bullet. I may make up a rifle for plain base on a low wall I have and I will try to find a gunsmith that understands the throats the plain base shooters use. I would also like to try breach seating. However, my interest right now is sort of like Pat's -- to see if I can get a gas check bullet (because that's all I have) to work in a factory chamber/throat without the gas check.

Col. Harrison in his landmark cast bullet articles in the Am Rifleman claimed that a gas check bullet would work as well as a PB bullet --as have others. But then he claimed CBs shouldn't be larger than the groove diameter so he didn't know everything.

I didn't expect instant success but the first try was worse than expected. I thought the PVC wad might make up for other sins as others claim it sometimes does for PB bullets but that was apparently wishful thinking. John

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tturner53 posted this 27 January 2013

Soft checks? Duane sent me a nice sample of these 'wax' sheets which I haven't really worked with much yet, but there is reports of them helping a lot in this type of load. My limited test hasn't proved anything yet one way or another but it might be something to try on those .22s.

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nimrod posted this 27 January 2013

I'm curious about fixed plainbase in factory rifles too we all know that the breech seated bullets work very well. I keep looking at the bullets used by the Schuetzen crowd no bore ride. 22 rimfire bullets no bore ride, I also look at the Hudson styled bullets that shot very well no bore ride. But he wasn't dealing with a 308 factory chamber. So I think that something along those lines a modified Loverin maybe smaller grooves and farther apart not unlike the LBT style bullet would be the direction that I would go. Oh well much to think about.

Richard

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frnkeore posted this 28 January 2013

Nimrod, My 22 rf bullet is a bore rider. F.W. Mann actually invented them (to my knowlege). He just called them 2 diameter bullets and that's what I call mine. .001 over bore dia. and .001 over groove. My base band is only .090 long on my 22 bullet.

The Hudson bullet is also a bore riding 2 dia. bullet. It normally cases .323 on the last 2 bands and .316 on the bands in front of them. for a .315 bore. It was made to BS in a reamed freebore for the 2 base bands.

I recomend 2 dia. bullets for fixed PB but you need a flat base not a GC base w/o GC. You have to seal the base of the bullet to keep it from gas cutting, at least at velocitys in the 1200 fps, up.

For BSing you don't need a special throat to shoot competitively, you do need a freebore and long throat for fixed. You need that to both center the bore riding section and the first base band. one band sized to be able to be pushed into the freebore and one band that's .001 - .002 larger than freebore to go in the neck of the case.

Frank

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frnkeore posted this 28 January 2013

In general, we shoot tapered bullets for BSing, usually .002 over bore for the first band and tapering to .001 - .002 over groove for the base band but, two dia. (bore riders) will also shoot BSed. I've shot 1.25, five shot groups at 200 yards with a 2 band, 190 gr, spitzer, PB, NEI bore rider. My rifle being a .308 groove, 32/35 Stevens caliber.

Frank