Gas check use, 357

mikerjf

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I'd like to ask the hive mind about gas checks.

I have a big box of Missouri Bullet 158g LSWC, .358, Brinell of 18, that I use for most of my target loads - really it's my general purpose 38/357 bullet.

I'd like to try some hotter loads using 2400, which I'm new to. Looking at reported results of say 1000 to 1300 fps, depending on 38 or 357 and barrel length (more interested in shorter).

Am I ok using my hardcast LSWC at this performance level, or should I be using gas-checks, or even go jacketed instead? I'd prefer to just use what I got if possible. Interested in any and all opinions, TIA.
 
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I have used hard cast bullets at velocities of around 1200fps. A lot depends on the alloy of the bullets you're using. I would recommend working toward your goal little by little, while monitoring the accuracy and leading.
 
If your bullets fit your guns you can run BHN 18 bullets to upper magnum velocities (But 18 isn't needed. I used 12 to 15 [15 for 9mm] for my 44 magnum near max loads, cleanly but I sized the bullets to the same diameter as the cylinder throats). I have a "Mystery Metal" alloy I use quite a bit for all my hand gun cast bullets and it runs 11-12 BHN. Gas checks help insure clean shooting and I have used them on some 429244s loaded max+...
 
On my attempts to use hard cast lead in 357 loadings I have gotten a bit more leading than I like. Mostly in the ends of the chambers but the forcing cone also gets leaded a bit. Nothing terrible and nothing the Lewis Lead Remover doesn't quickly take out, however I now use copper jacketed bullets for magnum loads and leave the lead for 38 specials.
 
It's no problem . I have for years shot full power 357 loads using cast bullets ( my own ) with softer hardness and some hard but w/o gas checks and have had no problem . I made sure my cylinder throats were slightly larger than the groove diameter of the barrel and no tight spots in the barrel , where the barrel threads onto the frame , where there is roll stamping on the side of the barrel . I have used IMR 4227 , I have used H-110 , Alliant 2400 and Ramshot Enforcer /Accurate powder 4100 also . I would have to say that I probably have used Alliant 2400 the most in 357 followed closely by H-110 , with nary any leading of the barrel and very good accuracy . regards Paul
 
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You don't need gaschecks; in fact, unless the bullets were designed to take them, you don't want them. If your bullets are properly sized you should get little to no leading.
 
I have used my own cast 158 gr Lyman bullets at a BHN of around 11-13 with minimal leading at any velocity. And some of my 357 Mag loads were really pushing it (15 grs of 2400). These included round nose, SWC flat base and SWC with a GC. I've also used commercial 158 SWC at 16 BHN and had terrible leading at lower velocities. These bullerts had a slight bevel base which I believe encouraged gas blow by which causes the leading. I think the bevel may be more for manufacture purposes than ballistic reasons.
Gas Checks really come into their own with rifle cartridges being pushed to well over 1500 fps with slower burning powders. They're are not needed for most handgun applications where velocities are way below1500 fps.

John
 
Good advice from the hive. Those bullets should shoot well as is... IF they are sized to the groove diameter of your barrel. THE MOST IMPORTANT FACTOR IN PREVENTING LEADING IS PROPERLY SIZED BULLETS. Get that part right and you're way ahead of the game.
 
As cowboy4evr stated above check cyl throats , you want them larger than groove diameter of barrel . Also check bore for tight spots . Both can be corrected & will make life much easier . Alloy hardness is overrated in handguns as BHN 12 or softer will handle vast majority of work . Lube & bullet fit are IMHO of primary importance , if these aint right you got leading . Classic plain based bullets for 357 are Lyman 358477 , 358429 Keith , Saeco 382 & HG51 . Gaschecked are 358156 , RCBS 38-158-SWC . 477 is explosive on varmits pushed hard , the Keith takes a little work & pushed hard can do anything sane with a 357 , Saeco & HG shoot well & are proven designs . Both GC are proven shooters & 358156 was a favorite of Skeeter Skelton . Newer Lyman molds have a rep for being undersized , HG molds are hard to find collector stuff & priced accordingly . Can't speak for the newer RCBS molds . New molds I'd seriously look at Mihec , NOE & MP .
 
I LIKE gas checks on my .357 SWCs for magnum level loads, but they may not be necessary. Partly just tradition with me at this point. A lot depends on your barrel, and your bullet to bore fit. If your bullets are at 18 Brinell, I doubt you'll have much problem.
 
On my attempts to use hard cast lead in 357 loadings I have gotten a bit more leading than I like. Mostly in the ends of the chambers but the forcing cone also gets leaded a bit. Nothing terrible and nothing the Lewis Lead Remover doesn't quickly take out, however I now use copper jacketed bullets for magnum loads and leave the lead for 38 specials.
I have found, my experience only, that cast bullets larger than cylinder throat diameter will result in "lead spray" leading on the cylinder face, frame and forcing cone. I size all my revolver bullets to the same diameter as the throats and get cleaner shooting bullets...
 
Thanking everyone for the great advice, and looking forward to trying 2400!
 
A quick note about 2400, it is a very accurate powder but leaves behind a significant amount of unburned powder residue. I recommend that you extract the empties in such a way as to avoid dumping powder behind the extractor, i.e. muzzle up.
 
I shoot rifle bullets without gc regularly between 1350 and 1550fps in rifles and a little over 1300 in revolvers without leading.Leading issue is more because the bullet size in too small than the hardness.Actually,when a bullet is too small,going to a harder alloy will only make things worse.
Bullet size is what matters most.Throat size is the thing to look for.That way you can go faster without leading.
 
You just need to try some work-up loads in your revolver & see how it goes. Guns are different, no set outcomes.

For me, in revolvers that wanted to lead, generally the slower the powder used the faster you could shoot them before leading became a problem, especially in the forcing cone, compared to markedly faster burning powders.

I liken it to starting off in your car in 2nd gear instead of 1st.

If your bullets are flat base (probably not if they are MBC's 357 Action model, which is beveled & frequently attributed to increased leading, verses flat base) I've defied convention & have used Lee's Push-Thru Sizing Dies to press on gas-checks to non-gas check flat base bullets, with good success.

.
 
Try what you got .
Elmer Keith didn't believe in gas checks , shot a lot of 44 magnum , plain based with a simple tin / lead alloy -
" for heavy & magnum loads at or over 1,000 fps use - 1 part lead mixed with 16 parts lead " ... taken from his book "Sixgun Cartridges & Loads" . This mix has a BHN of 11 . He also believed that bullet fit was more important than hardness .

I shoot a lot of soft alloy - BHN 8 , so use a gas checked design when loading to 1,000 and +1,000 fps . I read a lot of Skeeter Skelton and he used gas checks , especially on 357 Magnum loads , so I didn't develop a fear / loathing for them . I Got in on a couple group buy's and have bought enough checks to last me ... so I don't mind using them .

Hard bullets that are too small ... lead like all get out ... if your bullets are 18 BHN ...they have to fit throat and bore together .
Only one way to tell ... CHOOT EM' !
Gary
 
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I have shot 158 Lwc bullets in my M19 and 686 6" all the way up to 1320fps with Unique powder and never looked for leading, since most of these hot loads were for hunting and not many were fired in the field.

I always clean with a copper brush, so there was no need to look for leading since I cleaned the weapon until the barrel or cylinder had clean patches coming out.

I do know that my hot JHP loads did leave copper in the barrel, though.
Lots of "Blue" patches at the start of cleaning.
 

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