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gns4me
12-27-2006, 07:07 PM
Help.... this is the first time that I am fearful and worried. It goes like this......... Dropped good bullits from lee mold, (#90329 ?) its a .311 gas checked bullit @ 170 gns. I am sizing them in a Star with a .312 die. Its to just smooth & lube and seat gc. The gc. is on but not really tight (good tug with fingernail). I wantn to work up a load for the Mosin. Loaded win brass w/13 gns Unique and seat bullit to crimp groove. This puts base & gc. below neck. Well a bullit stuck in seater die and pulled out of shell but left the gc, in the powder. Now im worried that all 30 rnds. will drop the gc's . Will this cause a bad chamber rise if the gc. makes it to the neck in mid detenation? WHAT say ye all????

felix
12-27-2006, 07:10 PM
Not good. Reclaim them all. ... felix

gns4me
12-27-2006, 07:14 PM
:( Thats what I was thinking. Would it be alright to superglue the gc. onto the base of the bullit?

felix
12-27-2006, 07:18 PM
Yes, but that will get tiresome in no time. Best to get a die to lock on the checks, offline if necessary, i.e., a seperate operation on a cheap press/luber. ... felix

Leftoverdj
12-27-2006, 07:22 PM
Help.... this is the first time that I am fearful and worried. It goes like this......... Dropped good bullits from lee mold, (#90329 ?) its a .311 gas checked bullit @ 170 gns. I am sizing them in a Star with a .312 die. Its to just smooth & lube and seat gc. The gc. is on but not really tight (good tug with fingernail). I wantn to work up a load for the Mosin. Loaded win brass w/13 gns Unique and seat bullit to crimp groove. This puts base & gc. below neck. Well a bullit stuck in seater die and pulled out of shell but left the gc, in the powder. Now im worried that all 30 rnds. will drop the gc's . Will this cause a bad chamber rise if the gc. makes it to the neck in mid detenation? WHAT say ye all????

I would not worry about it hurting the chamber, but it won't help accuracy. If you are using old Lyman GCs, what you experienced is perfectly normal. They don't crimp on. You can junk them and buy modern checks, or you can use a cold chisel to throw up 4 burrs on the rim. Sizing will sink the burs into the shank and lock the check into place.

If you are already using modern checks, either you have a thin batch of checks or an undersized shank, which is not uncommon in Lee moulds. You can open up the shank area of the mould a couple of thous by coating the shank of a bullet with fine valve grinding compound and rotating it in the mould. Don't use power but a spare drill chuck makes a good handle to hold the bullet.

NVcurmudgeon
12-27-2006, 11:56 PM
First, I hope you are using Hornady, or other crimp-on GC. I don't think mould makers and GC makers like each other very much, or they don't seem to communicate! Luckily there is a simple solution. Anneal the GC by heating red hot, or a little less. If the GC are loose on the boolit, the annealing will prevent spring back and insure a tight fit. If the GC are too small to go on the boolit, annealing will make them easy to expand with a punch, again insuring a tight fit. Annealing can be done many ways. I use a wide, shallow tin can and heat it on the electric stove until the preservative coating on the GC turns black and flakes off. (If they go to red hot, that's OK too.) Let them air cool and they will be annealed.

gns4me
12-28-2006, 04:37 AM
The gc barely fit on the shank. I have to use a little brass hammer to get them tapped on. Then I will run them thru the sizing die but it being .312 I dont think that they are getting a good crimp onto the shank causing them to fall off. These are all good solutions that I may try to get them to work right. I was just worried about the pressure rise if a loose one tried to make it out of the shell or got stuck in the barrel. I guess I will pull them all and start over. Oh the gc's are an unknown. came from a friend who couldn't use them. Very old and of unknown mfg.

Bass Ackward
12-28-2006, 08:30 AM
Oh the gc's are an unknown. came from a friend who couldn't use them. Very old and of unknown mfg.

GCs will get hard just sitting around. And this probably explains why they are sooooooo hard to get on too.

Checks can become hard / stiff in as little as 2 years. The problem is that you don't know how old the age of the sheet metal or how long ago they were made. And even if they go on tight, are they as tight as they could be?

Annealing is a PITA step that results in better performance.

BABore
12-28-2006, 08:50 AM
Get yourself a 2 or 3 inch threaded pipe nipple, 6-8 inches long, and a couple of end caps. Pour the whole batch of GC's in and shove a wooden popcicle stick down the center. Screw on the cap and throw it in a wood stove, fireplace, or charcoal grill for a few hours. Easy to do in big batches. The popcicle stick is to burn off the oxygen inside and keep them shiny. TP works too.

felix
12-28-2006, 11:10 AM
These Gator checks for the current orders are made from brand new material from the rolling mill and should be tried without anneal first. Annealing is probably not needed as BA says, until they age for a couple of years. ... felix

9.3X62AL
12-28-2006, 11:44 AM
Dittoes to the above info. This sort of thing is what prompts me to use fewer and fewer gas checks as time goes on, although they are nearly a necessity in a lot of rifle applications. Their cost and their dimensional intransigence combine to annoy me at times.

Ricochet
12-28-2006, 11:55 AM
I'm having the opposite problem, with gas check shanks that are way too tight to get checks on. Not a problem with one mould, it's happening across the board, so it's something wrong with my casting technique. The boolits are generally too fat and taking too much sizing, too. I'm thinking I'm running the moulds too hot and need to slow down. It's caused me some real trouble, though. I broke the table my press was mounted on with sizing pressure, and after I moved the press to a new location I broke it again. Got to build or buy a sturdier one.

fourarmed
01-04-2007, 06:36 PM
Ricochet, that sounds really odd. Has it always been this way, or did it start recently? How hard is your alloy?

Ricochet
01-04-2007, 06:58 PM
It's been a problem for a while. I've had plain based boolits coming out a bit oversized, too. Several tumble lube designs are too fat to chamber the loaded round unless they're sized down. I've got ingots of scrap lead of uncertain composition but quite soft, mostly sheet lead and joints from sewer pipes with some tin refrigeration pipe, and ingots of wheelweights that I blend. Usualy I've got about 1/5 to 1/3 wheelweights and the rest the soft scrap. My boolits come out quite a bit heavier than the specified weights for moulds. I think my problems are that I've generally run the pot very hot, and cast fast, letting the sprue harden and frost, quickly cutting the sprues just a few seconds later and dropping the boolits, reclosing the mould and filling again.

As for the original question about the gas checks fitting loosely, but requiring tapping with a hammer to get them on: The lip inside the check is scraping the sides of the gas check shank of the boolit as it goes on, leaving it undersized. Either you're going to have to revise your procedures as I am to get the boolits to cast a little smaller, or you're going to have to expand the checks. (Something I really don't want to do, that's a good bit of added work.)

grouch
01-04-2007, 10:02 PM
It sounds to me like you've got a bunch of the old Lyman gas checks that don't crimp on. If you had crimp - on checks that started out tight on the shank there's no way they'd fail to crimp on tight enough that you couldn't thumb nail them off.

I suggest you either give them a try and see if you get suitble results or grit your teeth and buy a new box of Hornaday gas checks.

Hope this helps.

gns4me
01-05-2007, 05:50 AM
Well heres the results that I went with. Shot all but 5 of the reloads and had no bad signs. all were mild on the shooting and al least shot to point of aim. I then anealed the rest of the gc's and am waiting for the time to reload and shoot for groups. While reading Lymans reloading manual for more info found out that they say never to reload the shank of a cast bullit past the shoulder/neck bend. WHY??? does anybody know? Oh well off to the land of unknowns and viable research I guess.

I waant to thank all that gave thier time and knowledge to this thread. I learn by reading others trials ( errors and sucess's ) . then trying out my own.

Good luck and small groups. May the tinsel fairy stay far away.:Fire:

Oh yea forgot th o say that the gc's must be old lymans as there is no retension "burr" on the inside just a straight wall.

fourarmed
01-05-2007, 02:13 PM
Ricochet, I don't think the temp of your alloy is the cause. I'm guessing something is holding your molds open a little. Have you changed handles lately? Have you inspected your molds carefully to see if maybe some specks of alloy are stuck to the mating surfaces somewhere? Do you hold them loosely as they fill? What brand are your molds? I have some Lee molds that I have to tap every time, or they don't close completely.

Ricochet
01-05-2007, 10:08 PM
I've often found specks of stuff holding the mould halves apart and had to stop to get them out. I watch for any formation of fins on the bullets as an indication that's happening. Several of my moulds, especially the six cavities, are hard to get to snap completely shut. One thing I think I need to do with all of them is clean up old baked-on lubricant that was applied to the mould pins. That may have built up enough to be causing my problems.

HORNET
01-06-2007, 11:49 AM
gns4me,
The recommendation for not seating the gas check past the bottom of the case neck is because the old Lyman gas checks (among other old brands) did not lock on to the boolit, as you discovered. It is possible for these to come off upon firing under certain conditions. I had this happen with some .223's that my dad had loaded in 1978 when I shot them this past spring, fortunately without damage.
The gas check fell out on extraction and prevented the next round from chambering. It could have been much worse.:holysheep
The Hornady and Gator checks crimp in place and seem to be much more resistant to this occurrence.[smilie=1:
I tend to reserve the old Lymans, etc. for applications where the check will be inside the case neck and where accuracy needs are not critical since losing the gas check can toss that shot out in the weeds.:Fire: