.311041 1800 fps gas check or not

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  • Last Post 11 May 2012
Ben Cartwright SASS posted this 09 May 2012

I am new to cast bullets in rifles, I have military (issue and sporter) and have been shooting 173 grain bullets from a Lyman 311041 with gas checks. So far my most accurate load has been 15.4 grains of Unique, got a 1 1/2 group and 100 yards, but still working on it. A friend suggested I try them without the gas check. I haven't set up the chrony yet but am estimating they are going out there about 1700-1800 fps. Seems to me that I would risk getting leading at that speed.

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99 Strajght posted this 09 May 2012

I find I can not go over about 1200 fps without a gas check for any accuracy. Unique has never been a real accurate powder for me. Powders slower seem to be better. Try something in the range of 5744, Reloader 7, 4198 or 4895. 1 1/2 in is not bad. I also try to stay under 1800 with a gas check. Good luck.

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Dale53 posted this 09 May 2012

Most rifles will not tolerate speeds in excess of 1400-1500 fps without leading with a plain base bullet.

If would e most helpful if you would mention the caliber and make and model of the rifle when asking for information.

Someone may chime in here with more information if you give them something more to work with.

FWIW Dale53

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RicinYakima posted this 09 May 2012

I agree with the others, I can not normally get more than about 1400 f/s without leading even with a non-gaschecked design. And best accuracy in the 1250 f/s range. Once combustion gases start pushing past the trailing edges of the lands, you are going to have barrel leading.

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Ben Cartwright SASS posted this 09 May 2012

I am using a 1903A3 sporter with a 4 groove barrel. I tried 28 grains and then 30 grains of 5744 and had poor accuarcy, I estimated FPS at 1800-1900. I had heard of people using small amounts of 5744, but my Lyman book says the minimum load is 26 grains and it is safe to go below that? I looked at the Lyman book and chose Unique, first because it said 1500 fps for the minimum load of 12 grains and also because I had some. At 50 yards with 15 gr of unique i got one ragged hole but at 100 yards with the 15 gr it had a spread of about 4 inches, while 15.4 gr of unique was 1 1/2 inches, with 4 of the shots covered by a quarter. The Remington 9/43 barrel seems to like the unique, but I want to try other powders as well.

I have been told to never go below the minimum loads in the reloading books, is that valid for cast bullets?

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runfiverun posted this 09 May 2012

yes and no, it depends on the powder. in my 1917 i use the 311041 with gas checks. and 18 grs of 2400. <1900+ fps> by tipping the case to the primer when loading i can increase the accuracy somewhat. 1-1/2” groups for a rifle that specced out to 4"s almost 100 years ago is good. i hover around 2"s consistently and can bang the 8” 300 yd gong all i want, once i read the wind correctly. the rcbs 150fngc will do better at 100 yds but isn't quite as good at 300.

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99 Strajght posted this 10 May 2012

My best groups with that bullet in the 30-06 are

21gr 5744

18gr 4759

22gr R7

all are 1500-1600fps

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shastaboat posted this 10 May 2012

My load in 30-06 using 311041 (WW) 176.5 gr. with a gas check is 24 gr of 2400. Chronoes at 1975 fps. Accuracy for me has been about 1.5” at 100 yards.

Because I said so!

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shastaboat posted this 10 May 2012

runfiverun wrote: yes and no, it depends on the powder. in my 1917 i use the 311041 with gas checks. and 18 grs of 2400. <1900+ fps> by tipping the case to the primer when loading i can increase the accuracy somewhat. 1-1/2” groups for a rifle that specced out to 4"s almost 100 years ago is good. i hover around 2"s consistently and can bang the 8” 300 yd gong all i want, once i read the wind correctly. the rcbs 150fngc will do better at 100 yds but isn't quite as good at 300.

Have you chronographed your load? I'm loading 6 grains more powder and only get 1975 fps in a 24” barrel.

Because I said so!

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onondaga posted this 10 May 2012

http://www.castbulletassoc.org/view_user.php?id=5739>Ben Cartwright SASS:

Ben, Unique powder is a very fast burning pistol powder with a quick peaking high pressure curve to it's burn. That characteristic works well with cast bullets at low to moderate velocities but the pressures quickly overburden the ultimate compressive strength of cast bullets as you go higher in velocity/ pressure loads. Your 1700-1800 fps load is a top end pressure load that very likely would cause gas jetting and poor accuracy without gas checks on your bullets.

There is an alternative. I shoot a cast #2 alloy 170 grain FNGC bullet in 30-06 at 2100 feet per second using a powder from the opposite end of powder pressures. Reloader 22 yields much higher velocity combined with much lower pressure that doesn't even come close to a pressure that could cause gas jetting even if my bullets were plain based with no gas check.

The pressure of my load is less than 18,000 psi, the ultimate compressive strength of my #2 alloy is over 21,000 psi. A plain base bullet in #2 Alloy would easily hold up to that pressure and the soft start pressure curve of Rel 22 is very healthy to cast bullets and accuracy.

Rel 22 burn rate is 99 H4831 burn rate is 95 H 414 is 83 H380 is 81

Even H4895 at a slightly faster burn rate of 68 can be an excellent choice but pressures in the neighborhood  of the velocities you are hoping to get up to will require gas checks.

These are slow burning bulky powders with low pressure and smooth pressure curves that cast bullets really like.. If you want to go higher in velocity than 1800 fps and have pressures that #2 alloy can handle just fine without gas jetting, see if one of my suggested powders are recommended for your caliber and bullet weight. Then turn and run away from Unique and don't look back. I suggest the Lee 2nd Edition manual to search for loads with the powders I recommended as pressures in psi are listed for loads and the book has an excellent section on alloy strength and it's relation to loading pressures for cast bullets.

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shastaboat posted this 10 May 2012

Gary, Now it's time to step back to the 100 yard line....

Because I said so!

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onondaga posted this 10 May 2012

http://www.castbulletassoc.org/view_user.php?id=3261>shastaboat:   Brent, The site crashed while trying to enter my 02:20 PM post. I'm trying again.   I have tried the 1903A3 at 100 yards with that load. My vision will not accommodate open sights at 100 yards even with my new eyeglass prescription and a peep on my eyeglasses. The targets at 100 yards have clean bullet holes but groups are 3-5 inches and not consistent. It is not the rifle in my opinion, it is my fault.   I do have a scope and mount system for the 1903A3 but have not attached it because the mount system makes bolt removal for cleaning inoperative on the rifle. I am considering a different but more costly mount.

To this date, I have not used bullets matched by weight yet in the rifle. That may affect accuracy and tighten the group size a bit.   Gary

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Ken Campbell Iowa posted this 11 May 2012

a trick for old eyes....make the target ( bull  )  a lot bigger (g).

the group size really doesn't increase linearly with the increase of the diameter of the bull----and it beats having the bull fade out and move around on the paper   (g).

been there   ken

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shastaboat posted this 11 May 2012

Gary, I hear you on the eyesight. I can't hardly shoot open sights at all anymore and even with a scope and my glasses I get double reticles unless I have my glasses mounted right up tight. Try a 50 yard pistol target and see if that helps like Ken suggested.

Because I said so!

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