BHN range for rifle bullets

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  • Last Post 15 August 2013
Keith posted this 26 May 2013

I have started to cast for a 30-30 and will be using both plain base designs and gas checked. I have cast for revolvers for some time and have alloys that are 10 to 12 BHN. I have a good supply of linotype to add to adjust these when harder bullets are required for appropriate loads. Loading data for the caliber list velocities from 1200 fps to 2000 and the higher should require a higher BNH. I have read through my own references and the archives here looking for a suggestions on the range of hardness that would be needed but have not found anything definitive for rifle velocities and pressures. My question then is what is ideal range for BHN for both cast bullets in rifles for both plain base and gas checked that is optimum for preventing leading or an available reference?

Some details because that makes a difference. The rifle is a Ruger #1. This is a recreational rifle for range use and experimentation. Alloys are scrap lead of tested hardness and linotype. Molds my own and the generosity of others; Lyman 311042, 311291, and the RCBS 150 PB with others possibly to be added. Powders I have available in these times in sufficient amounts are Unique, 2400 and old Hercules Reloader 7.

Thank you for you thoughts. Keith DVM

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Ed Harris posted this 27 May 2013

Keith,

A simple approximation which will get you going with a high confidence of success is to take 3 (BHN x 480) as a good starting chamber pressure, and don't try to exceed 4 (BHN x 480) on the top end.

Based on this estimator 12 BHN works at 17,000-23,000

92-6-2 alloy at 16 BHN works best at 23,000-30,700

Linotype at 22 BHN works best at 31,700-42,200

This estimator agrees well with experience.

I use wheelweights with good results for plainbased loads and commercial “hardball” alloy mixed 50-50 with wheelweights for hunting loads with gaschecked bullets in cartridges like the .30-40 Krag and .30-30, where I want to load up to about 1800 fps with good expansion and where mild leading for a few rounds of carefully fitted and lubed bullets are not a problem.

With the powders you have 7-8 grains of Unique is in the right range for .30-30 with a plainbased bullet of 150-170 grains.( 170! TYPO CORRECTED)

With #2400 10-12 grs. work with plainbased and 13-16 grs. with gasechecks.

With RL-7 stick to GC bullets and your best target accuracy will be in the range of 18-21 grains, and you can use up to 24 grs. with GC bullets for hunting purposes.

With 150-gr. jacketed softpoint bullet 29 grs. of RL-7 approximates factory velocity.

73 de KE4SKY In Home Mix We Trust From the Home of Ed's Red in "Almost Heaven" West Virginia

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LWesthoff posted this 27 May 2013

If you have access to a good supply of lino, I don't think you can go very far wrong. I prefer lino for target competition with both my .300W Savage Production Class rifle and my 03A3 Military Issue Class Rifle. MV for all my most accurate loads run 1700 - 1800 fps. Any faster and I start losing accuracy. I notice you're not a CBA member. If you join, you'll get a lot of very good info 6 times a year on loads, powders, and most accurate MV's for the loads listed, for every load fired in sanctioned CBA competition.

Well worth the very nominal membership dues!

Wes

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CB posted this 27 May 2013

On the CBA website there are military match results posted. The load data for the 30-06, 7.5 Swiss, and 30-40 Krag will also work for other 30 caliber cartridges like the 30-30, 308, 300 Savage and 30 REM. Most of the loads are a medium reduced load and I find will work within about a 10% range of all these 30 cartridges, so I usually start at a 10% drop.

I find 20:1 lead:tin works good ( the softer bhn the better) for the couple of plain-base loads I have experimented with, and not over 1,200 fps. A tumble lube like Lee Liquid Alox or White Label 45/45/10 perform excellent in pb loads.........Dan

(I have had no luck in pushing Unique up much over 10-11 grs in 30 caliber loads. The pressure peaks rapidly and causes leading.)

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Keith posted this 03 June 2013

Thank you for the answers.

I had forgotten the about the formula for BHN and pressures. Even old cow doctors need to be reminded of doses once in while. The starting points for the powders and accuracy ranges are helpful also. This is again a recreational project and I intended to try different molds and alloys and powders once available. I have found that softer alloys are usually better but then all of my prior casting has been for revolvers. Enough linotype is on hand to give that a try also. I am a member of the association and read The Fowling Shot but often give my copy away to encourage others to join. This is a case where I wish I had kept copies or made copies of more articles.

Keith DVM

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jhalcott posted this 10 June 2013

You CAN over think this cast bullet thing! I use clip on wheel weights for MOST of my uses. I do not get into competition, but do hunt and plink with cast in several calibers. I have used straight linotype on occassion, especially in the .22 and 6mm calibers.This works OK for varmints,but can be messy on small edible critters. As far as the old articles, I'm sure there are those here that have them. Just ask!

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JeffinNZ posted this 25 June 2013

You know, the more I shoot alloy bullets the softer the metal I use. I started out, as I am sure many do, burning linotype because if a little bit of hard is good, a lot must be better. Just other day I was shooting the .30-30 bolt gun I have and the alloy was stick on WW with a splash of tin based babbit. BHN is just shy of 8 and with a gas checked bullet I am getting at least 1650fps and clover leaf groups at 50m. Now 8 BHN alloy doing 16-1700fps is a great hunting bullet!

http://smg.photobucket.com/user/JeffinNZ/media/Shooting%20stuff/50mCBE311_zps1d76ef2d.jpg.html>

Cheers from New Zealand

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apbluebass posted this 25 June 2013

Keith, How does one calculate pressure?

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LBD posted this 25 June 2013

http://www.castbulletassoc.org/view_user.php?id=7581>apbluebass wrote: Keith, How does one calculate pressure? There is instrumentation available to the hobbyist that requires one to attach pressure transducers to the rifle's chamber.  I think PACT makes such a device but since I'm cheap, I fiddle with QuickLoad and the data in the Lyman Cast Bullet Handbook.  Naturally, I make a lot of mistakes in trying to shoot the softest alloy possible, but that's part of the fun.

BTW, this is my first post and not to highjack this thread but I'm interested in finding out what alloy others are using for plain base bullet in the 30-'06.  COWW (clip-on wheel weight) alloy works pretty well in some cases but long term storage ruins their ductility; i.e., my last batch of bullets cast with COWW+a bit of softer Pb, increased approximately 4 BHN values just by sitting around for about 6 months.  I was able to restore them to BHN 11 by annealing but less than a week later they increased to BHN 12.

Anyway, what alloys and powders are you guys using for serious accuracy with PB .30 caliber bullets?  By serious accuracy, I mean < 1MOA out to 150-200 yards.  Beyond about 150 yards I expect some instability at these lower velocities, especially with my 190 grain .30's with .180” meplats and I realize better stability can be expected with more aerodynamic bullets, but I want to develop these loads for “varminting” with the '06 and 30-30.  I realize I could also paper patch and/or use a gas check design, but that's not my focus right now.  If I need to move or re-post to another forum, please let me know.

Thanks for listening, LBD

P.S. If anyone is interested, I designed the bullet molds mentioned above specifically for the '06, with an estimated BC of .380 or better, which reside in the Accurate Molds catalog. Links available on request.

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Keith posted this 26 June 2013

A few comments now that I have had the rifle to the range a few times. I like Jeff have found that 14 grains of 2400 works well with the Lyman 311041. More opens up the groups and they tend to string upward. The alloy I am using is in the range of 15 BHN. I usually cast in the range of 10 to 11 BHN for revolver loads and will be trying that next. What I am learning from reading and shooting is that just as in the revolver soft alloys are more forgiving and easier to find a accurate load with. If the bullet fits chamber and bore harder will work but it has to be right. My Reloader 7 has my father's hand writing on them dating them to 1988. They powder I am suspect is no long of use as I have been unable to get any accuracy. I will have to wait out the current shortages and try again with new powder. Plain base bullet will have to wait until there is more time for the range.

apbluebass: If you have a loading manual that give the pressure of loads and I thing the Lyman Cast Bullet manuals do you can use those pressures for the formula that Ed reminded me of. The intent of the calculation is get one in to the right range.

Keith DVM

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LBD posted this 26 June 2013

I've been using Richard Lee's formula for maximum chamber pressure which IIRC, is .9(BHNx1440). Unfortunately, accuracy has been hit and miss with 195-200 grain PB bullets. I have shot a couple good groups with 15.0 and 15.5 grains of WC-820 (AA#9) in Remington '06 cases (approx. 1400fps) but have not been able to reproduce the results by going up or down in powder burning rate while simultaneously adjusting charge weight. For example 16.0 grains of 4759 shot OK after a few foulers but after a single five shot group accuracy disappeared even though leading was not apparent. Also, fiddling with Blue Dot has shown some promise at 12.5 grains but at 13.0 accuracy disappeared again. I've made an effort to keep the velocity below 1450 fps with any and all powders while shooting PB bullets. Perhaps I'm just not using enough pressure for my alloys, which as I explained above, grow harder with age.

LBD

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badgeredd posted this 26 June 2013

LBD wrote Anyway, what alloys and powders are you guys using for serious accuracy with PB .30 caliber bullets?  By serious accuracy, I mean < 1MOA out to 150-200 yards.  Beyond about 150 yards I expect some instability at these lower velocities, especially with my 190 grain .30's with .180” meplats and I realize better stability can be expected with more aerodynamic bullets, but I want to develop these loads for “varminting” with the '06 and 30-30.  I realize I could also paper patch and/or use a gas check design, but that's not my focus right now.  If I need to move or re-post to another forum, please let me know.

Thanks for listening, LBD

P.S. If anyone is interested, I designed the bullet molds mentioned above specifically for the '06, with an estimated BC of .380 or better, which reside in the Accurate Molds catalog. Links available on request.

Welcome aboard...I think you'll like this forum over that other one...it seems there a fewer egos here.

What bullet did you design for a PB is the 06? I have been surprised with my accuracy results with PB bullets in a number of cartridges, but most especially in my little wild cat...30 Badger. One thing I have found with it is that if a bullet starts out right below the speed of sound, it stays stable for a long time, which I assume is due to the fact it doesn't go through the trans-sonic transition. Of course the trajectory becomes quite a rainbow!

Edd

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LBD posted this 26 June 2013

Hi Edd... thanks for the welcome.

Links to the two bullets referenced above:

http://accuratemolds.com/bullet_detail.php?bullet=31-185J-D.png>http://accuratemolds.com/bulletdetail.php?bullet=31-185J-D.png

http://accuratemolds.com/bullet_detail.php?bullet=31-185K-D.png>http://accuratemolds.com/bulletdetail.php?bullet=31-185K-D.png

The leading .040” long groove is a debris groove, not a crimp groove.  Since these designs are for a SAAMI '06 chambers, they're supposed to seat slightly above the .445” point (depending on cartridge case length and throat wear) when sized to .311".  Seated in this manner, part of the .14” long base would be below the neck/shoulder junction but the trailing lube groove should be completely contained w/in the cartridge case neck (at least with respect to my pre-64 M70).  I originally designed these two thinking I was going to have Tom cut me a 4 cavity mold with 2 cavities each and now I'm trying to decide which of the two to have a 3 cavity mold made first.  The reason I decided against the 4-cavity is because I use Rowell ladles and just noticed from Tom's photos how close the first cavity is to the sprue pivot on his molds larger than three cavities.  I'd be pretty much guaranteed to get alloy under the plate washer of his 2.9” and 3.45” molds no matter how they are mounted to the handles.  I talked to Tom about making a 4 cavity mold block with a different sprue plate but that would require additional jigs; i.e., more $$.  No big deal, I'll just decide which one I want to play with first.  A two cavity mold with one cavity each would currently be too time consuming for me at the casting bench.

The PB mold I'm currently using was cut for me long ago by MM and drops a bullet weighing about 198 grains in my alloy.  It's a bit more nose heavy due to its slightly longer ogive which is a tangent configuration opposed to secant config's possessed by the designs in the AM catalog and the meplat on my current mold is .2” in diameter (IIRC, the minimum allowed by MM at the time).  The 198 has shot pretty well with 15 and 15.5 grains of WC-820 but has shown what looks to be like instability on the target... perhaps I just haven't got the alloy/powder combo thing down yet with respect to PB .30's.

BTW, it's really warming up in So.KA this week but I still need to shoot a few groups next Monday with MML-Purple to see if I can reproduce my previous results with 15 grains of WC-820.  Hopefully my alloy will register a tiny bit softer than 14 by range day.  I think the last batch registered about 13 the day after casting so I might need to anneal tonight. Watching my bullets age harden even though they were air cooled is gettin' to be a pain in the rear.

Thanks again, LBD

P.S. Let me know if you think 31-185J carries too much lube... that's the one I'm think about doing first.

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jhalcott posted this 27 June 2013

LBD, you COULD just tumble lube these in LLA. You wont notice if too much is used. Since I am LAZY ,I DO NOT worry about a miss on a varmint(just means I sit in the shade longer!) I used the 30-06 and 30-30 (TC CONTENDER)for ground hogs for several years. Tried a bunch of molds and lubes,even teflon tape. I can relate to the frustration of NON repeating results. I BELIEVE mine were self induced though. Much of my alloy back then was “mystery metal” consisting of range pickups, COWW and scrap from work. SOME bullets were cast in the fall and loaded and shot the next summer. Welcome aboard, hope you enjoy the ride!

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LBD posted this 27 June 2013

jhalcott wrote: LBD, ...Welcome aboard, hope you enjoy the ride! Thank you.

http://www.castbulletassoc.org/view_user.php?id=1251>jhalcott wrote: LBD, you COULD just tumble lube these in LLA. I'm sorry, that would be against my religion.

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badgeredd posted this 28 June 2013

LBD,

Those designs remind me a bit of the Saeco #315. I modified a 311466 to kinda clone the Saeco mold. If you are concerned about lube capacity, I'd load 10 each, one set with both grooves filled and 10 with only the bottom groove filled.

One thing I have been noticing is that as our bullet lubes get better, one can use less lube with stellar results. MML is such a lube.

Edd

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LBD posted this 28 June 2013

So which one do you like better Edd, 31-185J or 31-185K? I haven't had either one produced yet; however, the calculated volume of lube that J will hold is about 20% more than K.

LBD

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LBD posted this 28 June 2013

To get back on topic... I'm going to load up some of my 198 grain bullets from my Mountain Mold tonight and I'm shooting for a BHN between 12 and 13 by Monday morning which is when I'll be shooting them with 15 grains of WC-820 (AA#9). If the targets meet my expectations, I'll post 'em here. I'll probably just shoot five from a cold, clean bbl, then a 10 shot group for the record. Lube will be MML-Purple and the shooting should be completed before the thermometer hits 90F.

LBD

P.S. Regarding the same alloy as above:

This time I baked at 400F for about 45 minutes and turned up the heat to 425F for the remaining 35 minutes and allowed the bullets to cool in the oven over night with the door closed. 2 days later they registered BHN 10 or a whole BHN value less than the previous annealing when I opened the oven door one hour after shutting down from 450F.  I'm going to test them again on the night of the 1st rather than shooting them that morning as previously planned.

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LBD posted this 03 July 2013

Well I finally got around to shooting some BHN 10 plain base bullets (from the 198 grain MM) with 16.0 grains of 4759.

The first 5 shot group after a fouler from a clean bbl was good... 5/8” C-C with 3 rounds in one ragged hole at 75 yards.

Unfortunately, the remaining three, 5-shot groups were just plain bad... mostly vertical stringing with shifting group centers. Stats over the chronograph were good (SD=9.5).

LBD

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badgeredd posted this 04 July 2013

LBD wrote: So which one do you like better Edd, 31-185J or 31-185K? I haven't had either one produced yet; however, the calculated volume of lube that J will hold is about 20% more than K.

LBD

http://accuratemolds.com/bullet_detail.php?bullet=31-185K-D.png>http://accuratemolds.com/bulletdetail.php?bullet=31-185K-D.png

 I like this one but that is totally my like and really has nothing to do with its potential. I suspect the radius ogive MIGHT be better.

ALSO, that babbit I sent you(?) ...we shot some PB bullets at our mini shoot last year with a balanced alloy (about 2% Sn, 1.9% Sb, 0.1% Cu),  air cooled in a 357 Magnum carbine at just under 1775 fps with no problems. I am guessing the added elements in the babbit had something to do with abrasion resistance...again that is a guess. The lube was MML BTW.

Edd

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LBD posted this 04 July 2013

Edd,

The only difference between the two designs (J&K) is the location and number of center driving band(s) and lube grooves.  When I designed the two, I wanted a mold that would drop a three-groove and two groove version with no other differences (the 2-groove version holds about 20% more lube).  Now I'm trying to decided which one to have cut first (in a 3-cavity mold).

Sorry, you must have me confused with someone else because I never received, nor was I expecting any babbit from you.  I do have a chunk of something very hard that resembles a Pb alloy I picked up at a plumber's estate sale... I wonder if it's babbit?? It's so hard I have been reluctant to add it to my pot.  Perhaps when I can get four or five consecutive groups to look like the good one in the attachment below, I'll experiment with it... assuming I can even locate it anymore!

Here are the first and second groups from yesterday. The range was 75 yards and the velocity, 1375 fps.  Next time I'm shooting for BHN 11-12 and 13 grains of Blue Dot.

BTW, the orange dot is 1.25” in diameter and I need that size dot to be able to see what I'm doing at 75 yards through my bargain 2x7 Leupold set on 6x.

P.S. My lube is always MML or some derivation thereof.  I think I'm going to drop the microwax for summers in the SW though.  When I start spending more time in NOV-FEB in WY, I'll put the BW-430 back into my winter lube and it'll probably be more like your lube.

LBD

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