.357 gas check?

alloy · March 30, 2010, 06:04 AM

Pulled this bullet the other day from a dud. 158 grain
I was told it was handloaded 10-15 years ago, but I have never seen bullets like this, is this what a typical gas check looks like?

If not, any idea what brand/type of bullet this is?

SL1 · March 30, 2010, 06:20 AM

Although it might be a copycat from another maker. I think Speer has quit making those. They were available to handloaders for decades.

Some like them, but I never did. At too low a velocity, they are said to be able to shed the jacket in the barrel. At high velocity, the nose just gets sheared off, without expanding the jacket, making a sort-of jacketed wadcutter with a somewhat rounded nose.

And, they seat deeper in the case than most jacketed bullets of the same weight, so they require reduced load data (which some early Speer manuals did NOT indicate, so there were some REALLY hot loads published for these bullets, probably well over SAAMI specs).

Modern jacketed bullets are far superior. But, some folks like these for reasons that they will need to explain for themselves.

By the way, gas checks are MUCH shorter, covering only about 1/8" up the side of the bullet from its base.

SL1

alloy · March 30, 2010, 06:36 AM

Quote:

Modern jacketed bullets are far superior.
~and~
gas checks are MUCH shorter, covering only about 1/8" up

OK
~and~
That's what I thought gas checks looked like, from the photos I've seen.

Thank you sir!

The cup seems very thick(reminds me of a teeny plumbing cap

), seemed like a reasonable idea, but I take your word to the contrary.

David Wile · March 30, 2010, 08:14 AM

Hey folks,

Fifty years ago there were a number of bullets generally available, and they included: jacketed, half jackets, cast, cast with gas checks, swaged, and paper patched.

Jacketed bullets consisted of a soft lead core swaged into a jacket that covered the length of the bullet right up to the curve of the bullet’s nose or even further - pretty much like we have today. Jacketed bullets included hollow points, spire points, round noses, and full jackets on the front with exposed lead at the base of the bullet.

Half jackets were usually found on pistol bullets and consisted of a soft lead core swaged into a jacket that only came about half way up the side of the finished bullet. The fronts could be round nose, semi-wadcutter, or whatever, but the all of the exposed lead was dead soft. A lot of folks considered half jackets as the worst of both worlds of jacketed and cast bullets. The soft lead exposed to the lands and grooves was not very kind to same.

Cast bullets and gas checked cast bullets were essentially the same thing other than the addition of a gas check to the rear of some. Cast bullets are made of some alloy of lead, tin, and antimony that made for a much harder bullet that would resist leading the barrel, unlike the dead soft lead of half jacket bullets. Cast bullets also have one or more lube grooves around them to hold lube which helps in reducing or eliminating barrel leading. Gas checks are simply copper or aluminum cups that cover about 1/8 inch of the bottom of a cast bullet, protecting the bullet base from hot gasses and allowing higher velocity than regular cast bullets. A bullet designed for a gas check also had a slightly smaller base band to accommodate the gas check. Cast bullets with and without gas checks are usually cast somewhat oversized, and they are then reduced to the desired size in a small press like machine that also applies lube to the grooves as the bullet is sized.

Swaged bullets can include anything from completely dead soft lead bullets with no jackets to fully jacketed bullets with dead soft lead cores. They are made with press and die sets capable of applying many tons of pressure. While virtually all reloaders use jacketed and cast bullets for their reloading, a smaller number of reloaders actually make their own cast bullets, and a very few number of reloaders actually swage their own bullets. Paper patched bullets are essentially undersized cast bullets which then are wrapped in layers of paper to make them the size desired by their users. It is a fairly small number of folks who use paper patched bullets these days, but it is still done.

They bullet shown in the picture looks like a full jacket bullet to me. The jacket looks like it covers the complete bearing surface of the bullet, so it would not be a swaged half jacket. It could very well be a non-commercially swaged bullet with a full jacket, but I would then consider it a jacketed bullet. It certainly is not a half jacket, nor a cast bullet, nor a paper patched bullet. I would guess that it was a full jacket bullet swaged by a reloader.

Best wishes,
Dave Wile

zippy13 · March 30, 2010, 10:26 AM

I recall when reloading catalogs included all the equipment necessary for home swaging and lead bullet wire was common. By the time I got into casting, the swaging gear was gone, when/why did go? And, based on the prices, may I assume modern gas checks are gold plated?

SL1 · March 30, 2010, 11:28 AM

I still have a few Speer bullets that look just like that one. I think they were referred to as "3/4 jackets". The intent was to completely cover the bearing surface to avoid leading, but otherwise have a soft lead core.

SL1

Brian Pfleuger · March 30, 2010, 11:33 AM

Is the base copper or lead?

alloy · March 30, 2010, 04:17 PM

It's copper, and very thick. Thicker than the top section of the bullet which I assume should not touch the bore of the barrel.

Picked it up at the range a week or two ago. Some guys had been there a with a sack of rounds they said some handloader had given them. 38 and 357. They said he had loaded them 10 or so years ago, They left 15 dropped or dud rounds laying there. Pulled them down, thought it was a kinda neat idea only one was like this.

GP100man · March 30, 2010, 04:29 PM

Speer discontinued those I think,I know they did the 44s

If ya down load it it`ll leave the 3/4 jacket in the barrel !!

A gas check is a cup that attaches to the base of a bullet that`s cast & the base is rebated for the Check.

Some bases are beveled & look like they`ll accept a check but they won`t !

Her`s a pic of the bulets I cast & you van plainly see the beveled, gas check& & the plain based bullets.

alloy · March 30, 2010, 04:48 PM

That's what i thought they looked like, have pondered them on gunbroker(my picture source for occasional questionable reloading lingo from here and elsewhere).
Thought it might have been some old type, or super-secret kind.

Or a plumbing cap.

dahermit · March 30, 2010, 05:35 PM

This is not a gas check. That is an early Speer jacketed pistol bullet. Shot lots of them in .41 and .44 magnums.

March 30, 2010, 06:20 AM	#2
SL1 Senior Member Join Date: November 8, 2007 Posts: 2,001	That looks like one of Speer's original design Although it might be a copycat from another maker. I think Speer has quit making those. They were available to handloaders for decades. Some like them, but I never did. At too low a velocity, they are said to be able to shed the jacket in the barrel. At high velocity, the nose just gets sheared off, without expanding the jacket, making a sort-of jacketed wadcutter with a somewhat rounded nose. And, they seat deeper in the case than most jacketed bullets of the same weight, so they require reduced load data (which some early Speer manuals did NOT indicate, so there were some REALLY hot loads published for these bullets, probably well over SAAMI specs). Modern jacketed bullets are far superior. But, some folks like these for reasons that they will need to explain for themselves. By the way, gas checks are MUCH shorter, covering only about 1/8" up the side of the bullet from its base. SL1

March 30, 2010, 11:33 AM	#7
Brian Pfleuger Moderator Emeritus Join Date: June 25, 2008 Location: Austin, CO Posts: 19,578	Is the base copper or lead? __________________ Nobody plans to screw up their lives... ...they just don't plan not to. -Andy Stanley

March 30, 2010, 04:29 PM	#9
GP100man Senior Member Join Date: August 1, 2007 Location: Tabor City , NC. Posts: 1,969	Speer discontinued those I think,I know they did the 44s If ya down load it it`ll leave the 3/4 jacket in the barrel !! A gas check is a cup that attaches to the base of a bullet that`s cast & the base is rebated for the Check. Some bases are beveled & look like they`ll accept a check but they won`t ! Her`s a pic of the bulets I cast & you van plainly see the beveled, gas check& & the plain based bullets. __________________ GP100man

March 30, 2010, 08:14 AM	#4
David Wile Senior Member Join Date: June 14, 2001 Location: Mechanicsburg, PA Posts: 585	Hey folks, Fifty years ago there were a number of bullets generally available, and they included: jacketed, half jackets, cast, cast with gas checks, swaged, and paper patched. Jacketed bullets consisted of a soft lead core swaged into a jacket that covered the length of the bullet right up to the curve of the bullet’s nose or even further - pretty much like we have today. Jacketed bullets included hollow points, spire points, round noses, and full jackets on the front with exposed lead at the base of the bullet. Half jackets were usually found on pistol bullets and consisted of a soft lead core swaged into a jacket that only came about half way up the side of the finished bullet. The fronts could be round nose, semi-wadcutter, or whatever, but the all of the exposed lead was dead soft. A lot of folks considered half jackets as the worst of both worlds of jacketed and cast bullets. The soft lead exposed to the lands and grooves was not very kind to same. Cast bullets and gas checked cast bullets were essentially the same thing other than the addition of a gas check to the rear of some. Cast bullets are made of some alloy of lead, tin, and antimony that made for a much harder bullet that would resist leading the barrel, unlike the dead soft lead of half jacket bullets. Cast bullets also have one or more lube grooves around them to hold lube which helps in reducing or eliminating barrel leading. Gas checks are simply copper or aluminum cups that cover about 1/8 inch of the bottom of a cast bullet, protecting the bullet base from hot gasses and allowing higher velocity than regular cast bullets. A bullet designed for a gas check also had a slightly smaller base band to accommodate the gas check. Cast bullets with and without gas checks are usually cast somewhat oversized, and they are then reduced to the desired size in a small press like machine that also applies lube to the grooves as the bullet is sized. Swaged bullets can include anything from completely dead soft lead bullets with no jackets to fully jacketed bullets with dead soft lead cores. They are made with press and die sets capable of applying many tons of pressure. While virtually all reloaders use jacketed and cast bullets for their reloading, a smaller number of reloaders actually make their own cast bullets, and a very few number of reloaders actually swage their own bullets. Paper patched bullets are essentially undersized cast bullets which then are wrapped in layers of paper to make them the size desired by their users. It is a fairly small number of folks who use paper patched bullets these days, but it is still done. They bullet shown in the picture looks like a full jacket bullet to me. The jacket looks like it covers the complete bearing surface of the bullet, so it would not be a swaged half jacket. It could very well be a non-commercially swaged bullet with a full jacket, but I would then consider it a jacketed bullet. It certainly is not a half jacket, nor a cast bullet, nor a paper patched bullet. I would guess that it was a full jacket bullet swaged by a reloader. Best wishes, Dave Wile

March 30, 2010, 10:26 AM	#5
zippy13 Senior Member Join Date: August 23, 2008 Location: SoCal Posts: 6,442	I recall when reloading catalogs included all the equipment necessary for home swaging and lead bullet wire was common. By the time I got into casting, the swaging gear was gone, when/why did go? And, based on the prices, may I assume modern gas checks are gold plated?

March 30, 2010, 11:28 AM	#6
SL1 Senior Member Join Date: November 8, 2007 Posts: 2,001	I still have a few Speer bullets that look just like that one. I think they were referred to as "3/4 jackets". The intent was to completely cover the bearing surface to avoid leading, but otherwise have a soft lead core. SL1

March 30, 2010, 05:35 PM	#11
dahermit Senior Member Join Date: October 28, 2006 Location: South Central Michigan...near Posts: 6,501	This is not a gas check. That is an early Speer jacketed pistol bullet. Shot lots of them in .41 and .44 magnums.