how hard can i push pure lino , h2o dropped in 308 win

[mike in co]

i have seen the recommendation for a max of 20k psi in cast boolits. that is with some alloy of common leads i assume...like maybe even ww h2o quenched. not sure.
but here is the question: how hard can i push a pure lino 311413( sized 309, 166.5 w/gc) in a 26" 308 win ( well its really a 7.62x51 palma match bbl) ?

with an oal of 2.757 oal, and 31 gr of varget i am at aprox 1950 fps at 20k psi.
(by the way these are some of the most consistant boolits i have ever poured....161.6 plus or minus .2 with just a couple outside that....)

mike in co

[454PB]

You should be able to get 2500 fps. You may even hit cartridge pressure limits before you hit cast boolit limits. I've fired .224 gas checked boolits at 2700 fps. and good groups. They are useless for anything but varmints, because they literally explode on contact.

[David R]

I have had 22 cal gas check boolits go 2700 with no trouble. Cast out of pure linotype not water dropped.

2200 for 30 cal using water dropped WW + 2% tin. Not a clue what pressure was, but the case was full of surplus 860. Accuracy was good.

Heck, my 44 mag has higher pressure than 20K. Its gotta be near 40,000 psi. Twenty somehing grains 2400.

I say just keep going up until you loose accuracy (hit the wall). Ya never know where the wall is. 308 is a great cartridge to cast and load for.

I shoot a stevens model 200 (savage 110) in 308. Its my second most accurate cast boolit gun. First is the 22-250, but I don't shoot that one much. Its a pain to mess with those tiny little boolits and my fat fingers.

David

[anachronism]

Linotype doesn't begin to obturate at 20,000. Pure lino begins obturation at about 31,000 psi. 20,000 is even low for the 44 magnum.

[mike in co]

so just keep going till it goes south ?
thanks guys

[1Shirt]

Yep, till it starts going south works for a lot of things including shooting cast!
1Shirt!

[stubshaft]

At least 2400 with Alox.

[leadman]

I pushed the 314299 cast of lino in the 30-06 to 2,600fps. Accuracy way good for 3 to 5 rounds, then had to run a patch or brush thru the bore. Accuracy was good at 1 to 1 1/2 inches at 100 yards, average for this Savage even with jacketed.

[JIMinPHX]

I've pushed a 23bhn Bator with moly lube in a .223 up to 3,000fps with no leading of the barrel, but lousy accuracy. My accuracy has been good upto about 2400fps so far, but I haven't done as much load testing as I really should, so there is probably room to go up from there. As long as you have a gas check, you can push them pretty fast.

[chemist308]

This thread is quite encouraging. I was honestly fearing I'd be limiting my 308 Win to being an old 30 cal squirrel rifle by going with cast loads. Looks like I need to find a lino or foundry lead source...

[felix]

225646, aged a year or better, shoots best at 60.5 grains naked, water dropped. Full lino drops at 56.5, and is not heavy enough for its length at 14 twist, at 2400. With strait WW, the mold drops at 63.0 grains. The Bator needs more of a point like the 225646 for anything close to 3000. I shoot the Bator at 2100 typically, and use it for the same "blow-up" as the faster shooting 225646 at the same distance. For better accuracy with the Bator at super speed, try and make the boolit tougher instead of harder as per the first sentence here. That means to do various combinations of WW and lino. I would seek a 50.0 grainer dropped, assuming the lino does 48.0 or less. Straight WW should make close to a 51.5 boolit. ... felix

[Bret4207]

so just keep going till it goes south ?
thanks guys

Same with any platform Mike. Each gun is an individual and no one "magic" component combination will give you the answer. Try it, observe, tweak, observe, experiment, observe... till you get what you want or hit the wall..

[mike in co]

99 pecent of my casting is ww/h20 dropped. these fill my needs. some 100 yd milsurplus rifle match shooting and some 44 mag pistol/carbine, 9mm, 40 s&w(soon to be 45acp). none of these are pushed hard, just "plinking" stuff. this is the first time i am looking at pushing the envelope on cast boolits.
the nice thing is my 311413 mold drops pure lino at 0.314 dia.....which means i can try it in lots of rifles. and yes i do have some pre mixed 3:1 ww/lino.

thanks

mike in co

[pdawg_shooter]

Size it .301/.3015, wrap it in paper and shoot as fast as you want to!

[Larry Gibson]

i have seen the recommendation for a max of 20k psi in cast boolits. that is with some alloy of common leads i assume...like maybe even ww h2o quenched. not sure.
but here is the question: how hard can i push a pure lino 311413( sized 309, 166.5 w/gc) in a 26" 308 win ( well its really a 7.62x51 palma match bbl) ?

with an oal of 2.757 oal, and 31 gr of varget i am at aprox 1950 fps at 20k psi.
(by the way these are some of the most consistant boolits i have ever poured....161.6 plus or minus .2 with just a couple outside that....)

mike in co

Mike

With 4895,4064,Varget and several other powders you can push it to 2700 fps just like a jacketed 168 MK in the .308W with a 26" barrel. However several things will limit you.

The Palma barrel, assuming a 13 or 14" twist will give you the best chance of higher velocity with some semblance of accuracy. It will do this because you will be able to keep the bullet within the RPM threshold. Those reading this with 12" twist barrels can push into the 2200 fps real with accuracy and those with 10" twists can maintain accuracy around 1950 fps. All has to do with the right alloy, powder, sizing and some other factors. The bullet design is also very important.

Unfortunately the 311314 design is not conducive to accuracy at high velocity although with the slower 13 or 14" twist you should get decent accuracy at higher velocity than a 12 or 10" barreled .308W will. With that bullet you might get decent accuracy up through 2300-2400 fps depending on the twist of your Palma barrel. Getting consistent accuracy at higher velocity and RPM requires a better designed bullet.

As mentioned many times straight linotype is not the best alloy for high velocity loads. It is brittle and I believe perhaps chunks chip off of the driving bands during acceleration. I get much better and more consistent accuracy with a slightly more malleable alloy such as a 80/20 or 90/20 linotype/WW alloys.

I use Javelina lube as my tests of HV loads in the .308W using 3 different rifles have not shown any difference between good alox/beeswax lubes and the hard wax lubes or the LBT Blue.

My tests also have not shown any improvement in accuracy over Hornady GCs so I use those.

My best accuracy comes with milsurp 4805 (close to Varget or 4064 in burning rate), RL19, AA4350 and H4831SC. Suggest you try those.

Attached is a fairly typical 10 shot group I get out of my 27.5” Palma barrel with a 311466 sized .311, lubed with Javelina, Hornady GC and 34 gr of the milsurp 4895 with a ½ gr Dacron filler. Velocity was 2519 fps and peak pressure wa 43,100 psi(M43).. 38 gr of RL19 or AA4350 does about the same. I can push this bullet (311466 cast of 90/10 alloy – 169 gr) up to 2650 fps with the first 3 shots (cold clean barrel) staying inside 1.5 moa and the 5 shot group running 2 moa. That’s a killer deer load but the barrel must be cleaned (easy; Hoppe’s #9, 5 passes with bore brush, 3 patches to clean) every 5 shots to maintain that accuracy. If not cleaned accuracy goes to 3-5 moa real quick.

Let us know how you do.

Larry Gibson

[runfiverun]

your boolit design is either gonna help you or kill you here also.
having gone back ane re-read he old rpm threads has helped me form a few opinions on the subject,
good bearing surface,very short bore riding nose and decent shape [goog b.c] will help you a ton.
lube will help or hurt too.
try one thing at a time tweak it some, try again. then move to the next,keep notes and only work on one project at a time. the slower powders that push all the way down the bbl help and a close to bbl diameter helps too.

[mike in co]

just back from the range. i had loaded these up from 19 to 27 gr of i4227.

these are sized .309, horn gc, rem 9 1/2 primers in ....lapua full prep'd cases.

used the 19's to get on paper.

shot the 25, 26, 27's only........well cause i thought the velocity would help in the 10-15mph winds!

25 was vertical, which typically means more powder, 26 was ok but two wild flyers i could not explain....combination of missing the wind and who knows.
i was using three wind flags.

the 27 averaged, 2225fps, es and sd of 11/4..................
5 shots right at 1.0x .......yes 100yds, yes 10-15mph winds,

i may have to try more powder or switch to 4064 or n135/n140.....hmmmmmmmmm

ohh and no leading, no grey muzzle.

thanks guys
mike in co

[pbbutz]

My go-to load for my 308 M70 factory target rifle(post64) is that 19 gr load of IMR 4227 with a LBT or RCBS 180. I have never found a better load for that gun. Never tried to shoot it any faster, just use j-word pills for that. Go slow and smell the flowers.

[shotman]

We do have some one that is honest Larry. Now I can beleive that group. I found the 413 does good "sized to.309" at under 2000fps. I would say a pure lino would be hard to size to .309. My mold drops at .313/.314 also and it is hard to push a WW boolit through a Lee. I loaded a few with 5577 and they seemed to do good in a 30-06 Garand. But I could not keep them in an in at 100yds with open sights, so I need to work in the load.Rick

[Larry Gibson]

Shotman

I know what you mean about sizing a .314 linotype bullet to .309, it is hard. It is too hard actually so I usually seat the GC, size and lube them at .314. I Then step them down through a .311 die and then the .308 or .309. Thaving the lube on makes them esay to size and also keeps the grooves intact. Aother problem i've encounter when sizing straight linotyp bullets down is small chunks ship off the driving bands. I can imagine this happening in a .308 barrel. The loss of those chunks has an unbalance affect on the bullet which is not conducive to accuracy, especially at high RPM. That's why I seldom shoot straight linotype any more. The above group was with a rather soft and quite maleable alloy of 6040 Linotype/WW. I have the same load loaded up with a 80/20 alloyed 311466 to see if that variable makes a difference. I already know that straight linotype does not shoot that well with that load at that velocity.

I, like many others know that linotype alloy can be extremely accurate at lower velocities. I have shot many thousands of linotype bullets (311284 & 311299s) in '06s at 1850 -2000+ fps so I'm not saying that linotype is not an accurate alloy. What I am saying is that in the instance of two bullets (311291 & 311466) shot at higher velocity (2500-2650 fps) linotype alloy alone is not as accurate as a slightly softer more maleable alloy. I suspect the chunks breaking off the driving bands during the bullets travel in the barrel as the reason. I've no real proof of that but based on my observations when simply sizing the bullets that is my guestimate at this point.

I'll point out also that the above group is typical of that load. Changing lubes during my extensive lube test did not improve accuracy either. Also note that 311466 is a Lovern design and is hardly "lube deficient". The friend who has the bore scope and has looked down many a bore was amazed at the bore in the 14" twist Palma Barrel. He says it is the smoothest bore he has ever seen.

Some say a really smooth bore is a deterent to cast bullet accuracy but yet this rifle shoots cast bullets as accurately as any rifle I've had at regular cast bullet velocities (1700-1900 fps) and shoots them much better at higher velocity because of the slower twist. I hadn't had any real opinion on this one way or another other than firelapping sure improves cast bullet accuracy in a lot of rough milsurp (not pitted but just roughly machined) and factory barrels. I also had a Anschutz (SP?) match .22 that had an extremely smooth lapped bore and it was accurate to say the least. It seems to me that the smoother the bore the less damage done to a cast bullet and the more balance it will be thus more accurate. Just my opinion at this time.

Larry Gibson