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Wardo1974
01-10-2016, 10:10 AM
I was reading Philip B. Sharpe's Complete Guide to Handloading last night, and read a couple hair-raising paragraphs that leave me concerned.

He recounted the story of a guy whose rifle barrel exploded. After examining the reloads the guy used, Sharpe came to the conclusion that it happened because the cast bullets the guy was using were checked; seating the bullets swaged the soft lead somewhat as the bullets slid into the case, and then the unsupported checks then dropped into the powder below. He'd fired a few shots and had a loose check get stuck in the barrel, and you know the rest.

I only recently started using checked boolits - I've always used plain based lead without issue. But I'm migrating to very soft lead in my loads and am going with the checks.

I HAVE noticed that simply seating a soft bullet swages the diameter by a thousandth or two. This has resulted in some creative work to get my loads to work with boolits that were once perfectly sized, but now weren't.

So now I'm worried about checks falling off into my cases. How likely is this to happen? Anyone else have this issue? I should comment that I only use cast in straight-walled cases like the .45-70, .38-55, etc. Is this more of an issue with bottleneck cases, or am I worrying over nothing?

MT Gianni
01-10-2016, 10:18 AM
The older Lyman checks were a slip on slip off fit. They changed them in the 80's. If you crimp modern checks on by running through a sizer you remove a lot of the problems of uncrimped checks shot from unsized panlubed bullets.

44man
01-10-2016, 11:28 AM
Do not use soft boolits that get sized seating. Gas checks should only be found after a boolit explodes on a steel target. You need to size them on a boolit.
Even if you shoot as cast and pan lube you must set the check in a die. Never use a die larger then the boolit diameter. If the boolit is .430", use a .430" die, NOT a .432".

Cap'n Morgan
01-10-2016, 12:21 PM
He recounted the story of a guy whose rifle barrel exploded. After examining the reloads the guy used, Sharpe came to the conclusion that it happened because the cast bullets the guy was using were checked; seating the bullets swaged the soft lead somewhat as the bullets slid into the case, and then the unsupported checks then dropped into the powder below. He'd fired a few shots and had a loose check get stuck in the barrel, and you know the rest.

Never say never, but it sounds highly unlikely that a loose GC should cause an explosion. A ringed chamber, perhaps, in the worst case scenario with the GC backup against the powder leaving an airspace behind the boolit, but not an explosion. My money is on the good ol' double charge.

quilbilly
01-10-2016, 12:36 PM
Never say never, but it sounds highly unlikely that a loose GC should cause an explosion. A ringed chamber, perhaps, in the worst case scenario with the GC backup against the powder leaving an airspace behind the boolit, but not an explosion. My money is on the good ol' double charge. I fully agree.

bangerjim
01-10-2016, 12:48 PM
I highly doubt a thin soft Cu GC would cause a barrel failure.

Always crimp/seat your GC's with a sizing die. These people that try to skip the sizing die that are using GC's are just asking for them to come off somewhere besides downrange. Take the extra few seconds and run them thru the sizing die. I use Lee push-thru's with great success. You want the GC to be the same size as what your boolits are being sized to.

They may "snap on"......but they will also "snap off" where & when you do not want them to!

bangerjim

44man
01-10-2016, 01:22 PM
Never say never, but it sounds highly unlikely that a loose GC should cause an explosion. A ringed chamber, perhaps, in the worst case scenario with the GC backup against the powder leaving an airspace behind the boolit, but not an explosion. My money is on the good ol' double charge.
Or a stuck boolit in the barrel.

runfiverun
01-10-2016, 01:32 PM
if I were working with soft material that squished down and stayed there, and another material that sprung back form being squished down.
I would anneal the one that sprung back to make sure it didn't.

big bore 99
01-10-2016, 02:01 PM
Although, this seems like a long shot, I still worry about it. I've switched over to paper patching in my 45-70's.

hickfu
01-11-2016, 02:32 AM
Ive had gas checks fall off when I used Hornadys but since switching to gator gas checks... none have fallen off

44man
01-11-2016, 09:00 AM
I have not hit dimensions right a few times and checks were loose. I lap that portion of the mold for a better fit.
Then I have made them too tight too and I need a small hammer to get the dumb things on.
My RD mold is too tight so I made a nose punch in an old RCBS die, set the check and boolit on a Lee sizer ram and squeeze them on.
My boolits are tough enough to not deform.

bedbugbilly
01-11-2016, 10:44 AM
Doc - not debating or challenging what you are saying . . . I'm just getting started with GC. What is the difference between a Hornady GC and a Gator GC? In looking at a Hornady illustration - they appear to have what I would call "detents" in the upturned lip which would crimp into the base of the boolit. Does the Gator have similar design or what makes it "hold" better? Thnx.

Rizzo
01-12-2016, 01:53 PM
New to Gas Checking and wonder...
If you tumble lube the cast bullet prior to sizing....which one normally does, will the lube have any effect on the gas check when sent through the sizer? It seems like the GC would not be on as tight as compared to no lube.

hickfu
01-12-2016, 01:58 PM
Doc - not debating or challenging what you are saying . . . I'm just getting started with GC. What is the difference between a Hornady GC and a Gator GC? In looking at a Hornady illustration - they appear to have what I would call "detents" in the upturned lip which would crimp into the base of the boolit. Does the Gator have similar design or what makes it "hold" better? Thnx.

Since I do not have any of the Hornadys laying around any more I cannot verify this but I think they are just a little smaller then the Gators. But I do crimp them on and size using a .460 sizing die so that may be why the Hornadys dont work for me. Maybe the Hornadys are for something in the .458 to .459?

vzerone
01-12-2016, 02:58 PM
One should expand his case neck to the right inside diameter. If that is done I don't see how even a soft bullet would size down some. This is why, too, I like the RCBS expander type system because it starts a gentle flare. Lyman M type leaves an abrupt shoulder. Nobody will ever convince me that Lyman didn't make that type of expander for being able to set flat base j-words in the case neck just like how a boattail sets in the case neck without falling out. Then you have your loading tray full of ready to size bullets. Then Lyman seen the cast bullet seating styles that we use to start our bullets easier, such as the old needle nose pliers trick, or a 50 cal bullet trick, etc, and they started advertising it as a cast bullet tool. I'm not buying it.

The crimp type checks stay on pretty good providing the initial fit wasn't real loose. I make my own check, mainly from aluminum, and I'm not having a problem with them coming off. I find bullet remains in my back stop dirt with check on them and that's even after passing through the wood target holder and some of the back stop dirt.

Sensai
01-12-2016, 03:01 PM
All of the above is true, for bottlenecked cases. Checks will not come off in a straight walled case. How could they unless they were smaller in diameter than the bullet? Even if they could, you couldn't create a problem unless there was a tremendous amount of empty space in the case. In a straight walled case all of the powder, therefore the pressure, will be behind the check. This will cause the check to be pressed harder onto the bullet, at least until it leaves the muzzle. The theory that a check could be lodged in the bore is based on the check being so far down in the powder that the pressure can force the bullet down the bore ahead of the check, with just enough powder behind the check to force it only part of the way down the bore. I don't buy it!

bedbugbilly
01-12-2016, 03:38 PM
Thanks Doc - appreciate your reply!

zomby woof
01-12-2016, 07:35 PM
I had some 125 9mm that I cast too soft. I tried some soda can checks with super glue. They stopped the leading. However, when I was sweeping up in front of my shooting position, I was sweeping up gas checks. They were coming off right out of the barrel. I'm shooting them in my 38 spl slow now

vzerone
01-12-2016, 08:01 PM
I had some 125 9mm that I cast too soft. I tried some soda can checks with super glue. They stopped the leading. However, when I was sweeping up in front of my shooting position, I was sweeping up gas checks. They were coming off right out of the barrel. I'm shooting them in my 38 spl slow now

zomby woof I think you would like Freechexs, but the ones sold to make a gas check. This is different. I'll try explain. You modify your sizer die in your Lyman type luber/sizer and you cut discs from soda cans and you place one in that modified die and you check, lube, and size your bullet in one stroke. Now my method you don't touch the die. I make a ring that fits precisely inside the nut that holds the die done. The hole in it is the size of your unsized bullet. On the underside of that ring I cut a recess about the thickness of the soda can material. That recess is the size of the discs you cut which by the way you figure how out by how far up the sides of the bullet you want the check to be. Don't go too far as you will get wrinkles. I stick the disc to that recess with a touch of lube to hold it, place it in the die nut, place a bullet in the ring (the ring centers it with the disc and die opening) and size, check, lube your bullet. Much much much easier when you see it then explaining it.