Sponsored Research

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  • Last Post 06 September 2018
John Alexander posted this 31 August 2018

See frnkeore's suggestion for this thread in his post today to the thread "Small Cases are not Better".

The idea is to cooperate to support some research targeted at the principles of cast bullet shooting that are still a mystery with lots of opinions, theories, and strong beliefs but based on little solid evidence.

To get it out of the "good idea" stage will take work in organizing things.  A shooter who would like to tackle a topic and is willing to pay for half or more of the expenses could propose a design for answering the question. I think it would take a working group to select one or more proposed studies that have the potential to answer one or more useful question, talk up the project, receive donations from shooters curious enough to put some money where their opinions are, receive a report from the sponsored experimenter to be published here in in TFS, and otherwise see that things worked.  

Anybody interested or at least interested in discussing?

John

 

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dbarron posted this 31 August 2018

John: I'd like to help with this. I'd support with donations as well.  superb idea.

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Scearcy posted this 31 August 2018

John

I think the idea has merit but the devil would be in the details of course. Many of the old wives tales we argue about endlessly may not help accuracy but most do not hurt accuracy either. So then do they deserve much effort? According to Joe's math the individual impact of these practices, which may or may not offer SLIGHT improvement, are likely too insignificant to even measure. 

On the other hand we have factors that require time and money to the extent that making a wrong choice can be significant to a competitor. Case size is a good example. Twist rate is another. Bullet profile and hardness (should I say toughness) can take months when pursued by the individual shooter. I would offer the hypothesis that there is an optimal BC / alloy / velocity combination for any weight of rifle. This would be difficult to pursue but very much more interesting than shooting the bullets in the order cast, etc.

Here is one of my favorites: is the benefit of a bumped bullet and a throated chamber even real given equal equipment. If it is real, does the benefit accrue from the process of bumping the bullet, throating the rifle, or only when you do both. 

There are several others but I have gone on too long already. However, we must have a talented individual(s) out there who can devise a readily accessible methodology for breech seating in a factory bolt gun.

Jim 

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Ross Smith posted this 31 August 2018

I'd like to see more proposals on what to test. I think I'm better or the "worker" end of things.  I am planning on doing some breach seating in my 2 30-06's. So far just a push type seater and mallet. That does damage the bullet base. Ross

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frnkeore posted this 31 August 2018

I'd also like to see one done on throating, by itself.

BTW, I think that we should develop a "standard" set of rules for accuracy testing.

Such as a minimum number of rounds tested, blind test and using two different shooters, so that accuracy can be comparable.

For both a case and a throating tests, you might contact reamer manufacturers and see if they would be interested in supplying the reamers, for credit given, plus a free add or two. Do that also for materials for other projects.

Frank

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stevebarrett posted this 31 August 2018

I'd be interested if it extends to handguns.

Steve

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Shopdog posted this 31 August 2018

Due to legal requirements I don't work on other folks guns but,if you need any machine work done on test fixtures or handloading tools.... I'll donate shop time and some parts.

Being as my interests are varmint rigs.I would be more concerned with day to day POI changes and cold bore predictability than 10 shot groups.

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MarkinEllensburg posted this 31 August 2018

I think this is a great idea.

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Ken Campbell Iowa posted this 31 August 2018

LET US DEFINE OUR GOAL(S):   we only have one rabbit ...we need to find the right rabbit hole. 

proposal after little thought ::

1.  since no factory is going to ever build an optimized factory rifle for cast, we don't need to put CBA * TEAM for ADVANCED  RESEARCH in CAST SHOOTING  * ( TARCS )  effort into researching factory rifle cast  predictability.  We would expect fallout benefits however.   

2.  TARCS effort should be directed into things that we regular shooters cannot do at home.  we can play with small variations in components, alloys, etc., and give statistical numbers to any possible discoveries unearthed by the TARCS ... 

but we cannot cut molds, cut chambers, cut forming/swaging/bumping dies, and buy 6 identical ( almost) barrels from Lilja  to do controlled experiments with.

So ... we should be focusing on creating from scratch the optimum  equipment to shoot cast most accurately .....   with our resourses this cannot be a universal search for universal results.     >FOCUS .

maybe if we each submit 3 specific things we would like to see ....  we can statistically match the overlaps and that would be a good suggestion to the TARCS to begin their query.

Time to end this note, i am starting to think about it. ( g ) .

ken  

 

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Scearcy posted this 02 September 2018

Ken

You caused me to question some of my my most proud possessions - opinions. You often do, thanks.

My bias (I spelled it right) has always been to work with stock factory rifles. I have too often spoken bitterly against the equipment races inherent in competition. Having said that, my bias (that word again) is toward increased participation. Playing with 18# $3,500 rifles could be an interesting exercise but it is highly unlikely to hold much value for the new shooter we are trying to recruit. And yes I know we are dedicated to the pursuit of ultimate accuracy with cast bullets. Our Region 5 Heavy rifle records  for 5 shot and 10 shot groups are respectively in the .2s and .4s. What are we really going to do with those numbers that is of interest to a new shooter. These records are held by a professional machinist BTW, may he rest in peace.

What is my point? I do believe that there are certain bullet designs that are consistently among the top choices such as the 311299 but only in the 3 most popular diameters. There is an as of yet unresolved argument regarding well designed bore ride vs single diameter bullets. Many bullets can be made to perform better with the help of a simple taper die but there is no readily available source of 30 cal taper dies let alone dies for the sub calibers. I continue to believe that carefully "bumping" the bullet is more important than throating the rifle. Breech seating - we know it works but have no accessible methodology to apply it in bolt action rifles. I don't know that we have more than scratched the surface regarding powder coating. The black rifle and handgun guys are out ahead of us on this one. ETC.

I am not trying to be controversial. My argument is that there is more benefit for the CBA if we can help 10,000 shooters improve from 2" groups to 1" groups than there is if we devote our efforts to helping 25 shooters reduce their groups from .5" to .45". 

I welcome discussion of course but please keep it directed at my ideas rather than my questionable parentage. Ken this comment is not meant for you my friend.

Jim

 

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Paul Pollard posted this 02 September 2018

http://www.mountainmolds.com/

Check this for 30 caliber taper dies. Click on 30 cal designs; two different angles.

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Brodie posted this 03 September 2018

Ken Campbell said, " So ... we should be focusing on creating from scratch the optimum  equipment to shoot cast most accurately .....   with our resourses this cannot be a universal search for universal results.     >FOCUS .May I suggest that if we actually get around to doing this we buy a Savage M 12 long action, because I believe that you can swap out the bolt face for a .223 or 300 BLK case head size, and then back to the original .308/ 06 head size and thus rechamber the 30 cal barrel for each cartridge as we go along.  It would make a good test of the case size question.  Uniformity in rifle , trigger, stock, barrel and the biggest variable would be the size of the case.  You could even go one further and include the 300 Win Mag if possible.

B.E.Brickey

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OU812 posted this 04 September 2018

Compairing large case capacity to small. You could chamber one barrel 308 Winchester and the other in 308 Short. The 308 Short chamber requires cutting chamber .250 shorter and shortening reloading dies .250". You could have reamer made using 1 degree taper per side throat angle (or what ever angle you choose)

You can shorten most any case simply by cutting resizing and collet die shorter and rechamber cutting chamber shorter.

Must read:

https://www.go2gbo.coms/89-wildcat-cartridge-discussion/362609-308x45-project-30cal-hunting-round-recoil-shy-kids-elderly.html

Quote from link: "Waiting for my Barrel and Dies to be Delivered 

George has done all the work on the barrel and dies, and I asked him to send the barrel post-haste because the idiot Commiefornia legislature passed or are on the brink of passing a dumb-ass gun parts law that they must be transferred thru an FFL, so I don't want to get stuck. "

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OU812 posted this 04 September 2018

Testing short vs. long.

You could chamber barrel shorter to begin with using the 308 Short then test firing several rounds (200 rounds maybe). Next rechamber deeper to 308 Winchester and repeat test using same barrel.

Picture taken of 30 BR (cast bullet) chamber.  This is the only 30 cal. cast bullet chamber they show in PTG book. You could have 308 Winchester reamer cut similar. 

 

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joeb33050 posted this 04 September 2018

If you want to compare a and b, I like the Ardito method.

Chamber 1 end a, and the other end b, ex: 1 end 308 and the other end 30br.

screw either end to the action and shoot.

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pat i. posted this 04 September 2018

I shot next to Ardito at a nationals and he had a barrel chambered on both ends. The gun itself looked like it survived the Hindenburg disaster. It did get some notice and maybe it was his way of telling people to not get too wrapped up in all this stuff.

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OU812 posted this 04 September 2018

Would using the same reamer to cut both chambers (308 Winchester, 308 Short) be a more accurate test. Both throats would be identical.

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M3 Mitch posted this 05 September 2018

Would using the same reamer to cut both chambers (308 Winchester, 308 Short) be a more accurate test. Both throats would be identical.

I would think this would help, but I can't prove it.

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frnkeore posted this 05 September 2018

The taper on the body of the reamer, makes a difference.

If you where to use the above, 308x45 as a base, the 308 Win length would be .003 large at the case head (exceptable) and .003 small, for the 30 BR length but, that could be polished enough to use.

The 308x45 drawing is a cartridge drawing, not a chamber drawing. Chambers run approx .001 larger than cartridges (gotta get um in somehow, as Ken might say).

Note that the SAMMI chamber is .471 @ .200, it doesn't need to be quite that large, at that point. All modern cartridges have that datum @ .200, that is the approx location of the solid head and for modern brass, in a match chamber, that point can be .469.

Also, note that the SAMMI tolerance, is +.002 so, that can help with using one reamer.

Frank

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Lee Wiggins posted this 06 September 2018

Gentlemen,

   John Ardito wrote an article "A Case For Cast" a long time ago. It will take some digging for me to come up with the FS # it was in.

He started by chambering for a very short 308, tested, ran the reamer 1/8 in. deeper , tested, and repeat all the way to full 308 or just short of full size. Same rifle, barrel, everything. His conclusion was that 308x 1.5 was good ( This is my comment ,same case capacity as 30BR) but he liked the 308x1.625 better.

   A lot of the research on this has already been done.    Lee Wiggins

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