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XWrench3
03-25-2020, 05:10 PM
so, i bought a 200 grain lee mold (.30 caliber) to shoot out of my 300 win mag. the question i have is seating the boolit anywhere even close to 3.340" (standard max length) will leave the gas check basically "dangling in the case" (yes, i know its crimped). but it is a concern that it could be knocked off during firing or under recoil in the case of cartridges in the magazine. am i worrying for nothing, or can this actually happen?

Bazoo
03-25-2020, 06:31 PM
My concern is always of the lube that's exposed inside the case. I imagine powder sticking to it like dirt on a dropped lollipop. Or it warming up and contaminating the powder. Or the pressure from firing blowing it off in the case somehow and running the bullet naked down the bore. I don't think the gas check coming off is an issue if it's a crimped on check.

Misery-Whip
03-25-2020, 09:23 PM
Could always add a drop of superglue before criming it on.:kidding:

Recover fired rounds and know for sure.

s mac
03-25-2020, 09:28 PM
Another possible scenario is the base riveting. Something to consider.

XWrench3
03-26-2020, 09:59 AM
"Another possible scenario is the base riveting. Something to consider."
I actually thought about that. but i have no idea without a lathe how you would ever get dead center. i also thought about glue (epoxy), but i can not even imagine how badly the squirting out glue would mess up the sizing die. super glue dries into a hard crystalline structure, that would most likely be shattered by the firing of the round, and therefore be useless. i am not concerned about the loss of the check, i am worried about it being left in the bore, and firing another round. i have had a bore obstruction, and ruined a barrel. thankfully, the damage to me was only financial. i know i have a great guardian angel. but next time, he or she may be sleeping, or out to lunch!

s mac
03-26-2020, 01:02 PM
My reference to base riveting is during the firing sequence, pressure riveting the base before it gets to the neck.

Bazoo
03-26-2020, 02:45 PM
It's a pretty common practice to superglue checks on when using the old style ideal/Lyman non crimp on checks. I don't think firing would break the glue bond as it would be a compression load and not a shear load.

MostlyLeverGuns
03-26-2020, 03:24 PM
Pressure inside the case is equal on all surfaces within the case, pressure on the sides of the bullet are the same as the pressure against the base, the bullet cannot rivet from pressure only on the base. Hitting the base of a bullet with a hammer yes, gas pressure inside a container, not so much. Bullets may obturate or upset when the bullet hits the rifling, but this different from riveting. When loading the the 300 Win Mag and 300 Savage, bullet shanks and gas checks commonly extend beyond the neck and accuracy can be very good. Depending on many variables, powder, pressure level, bullet fit, some heat/pressure damage can affect the part of the bullet exposed to the powder gases above the gas check but this is not usually a problem until velocity and pressure is above 'usual' cast bullet range (1800-2000+ fps). Mostly such problems show up as loss of accuracy noticed well beyond 150-200 yards.

s mac
03-26-2020, 03:32 PM
Pressure inside the case is equal on all surfaces within the case, pressure on the sides of the bullet are the same as the pressure against the base, the bullet cannot rivet from pressure only on the base. Hitting the base of a bullet with a hammer yes, gas pressure inside a container, not so much. Bullets may obturate or upset when the bullet hits the rifling, but this different from riveting. When loading the the 300 Win Mag and 300 Savage, bullet shanks and gas checks commonly extend beyond the neck and accuracy can be very good. Depending on many variables, powder, pressure level, bullet fit, some heat/pressure damage can affect the part of the bullet exposed to the powder gases above the gas check but this is not usually a problem until velocity and pressure is above 'usual' cast bullet range (1800-2000+ fps). Mostly such problems show up as loss of accuracy noticed well beyond 150-200 yards.
Now that makes sense, thanks for posting this.