LC brass not fitting

[pittbull46]

I just put a new barrel on my 10fp and set the headspace with a go gauge I can get a win case to chamber easy but the LC case closes real hard they are both once fired out of the old barrel can anybody help thanks

[stangfish]

When you are talking unfired cartridges the LC is 7.62x51. The dimensional tolerences are a little different between that and the 308. Most people who use LC brass full length resize, anneal if they have the ability and trim to 308 win oal dimensions before putting them in their 308 rifle.

To answer your question specificaly...
If they have been fired in another barrel and your chamber is shorter, then you need to full length resize slowly adjusting the die untill you bump the shoulder back far enough for it to fit your new chamber. Be careful to not oversize or move the shoulder too far back. A case headspace gauge would be benificial at this point but not required. I always suggest that due to the fact that it is a simple way to start seeing the relationship between case dimensions and accuracy. The next step is a stoneypoint where you can see the effects of the relationship of the bullet ogive to the lands impact on accuracy.

[pittbull46]

Could you explain how to adjust the die I did FL size the LC brass I am using a lee FL die and have the neck die also and what do I do with the headspace gauge

[geargrinder]

Answer a few questions and we can give you some solid advise.

How is your FL die set up now. Is it screwed all the way down so that it touches the shell holder?

The win case you were using. Has been fired, or is it new?

Have you FL sized the LC brass? If you have, have you checked the trim length?

What brass are you going to use in this rifle? Win, LC, or a mix?

[pittbull46]

Hello The die is 1?4 turn past the holder the win case has been fired in the old barrel I FL sized the LC case and cut the lenght to the win brass I have both kinds of brass more LC heard the win was better and could get more powder in them

[geargrinder]

Annealing the LC may help get it sized so you can chamber it easier. It may not be worth the trouble.

[ellobo]

Put your LC brass butt down in a pan of water a half inch deep. Heat the brass to red and tip them over into the water. Thats annealing. LC brass is thicker than Winchester so neck turning may help them chamber after loading with bullet.

El Lobo

[MikeCTX]

Good advise already - you ask what you should do with th go-gauge. Would guess you used it to headspace the barrel when you put it on. Did you add a strip or two of tape to treat it as a no-go gauge? It does work, with all of that out of the way next step would be to measure the oal of the win case andthe LC case, are they the same? Not sure about the 7.62x51 LC brass, but I just had 1000 LC 223 (223 not 5.56) barss delivered and you can see that it has all been annealed - so point is if the brass has already been annealed, I do not think that is needed or will help (and may hurt). If you can find a Wison case gauge (they make on in 308) is will help you verify that the LC brass is sized correctly.

Good luck and hope you enjoy the new barrel.

[Aircraftmech76]

Put your LC brass butt down in a pan of water a half inch deep. Heat the brass to red and tip them over into the water. Thats annealing. LC brass is thicker than Winchester so neck turning may help them chamber after loading with bullet.

El Lobo


If you heat brass to that degree, you have over-annealed. The annealing mark should progress just below the shoulder/body junction. If he gets that kind of heat down to withing a half inch of the base of the case, he's gonna be wearing metal.

[pittbull46]

Thanks for all the info I just thought I did something trying to hs the barrel I think I will just get new win brass thanks again

[earl39]

what is the headstamp on your LC brass? It may have been fired in a machine gun and need to be sized with a small base die. I am not telling you to run out and buy one but if you know someone that has one try it on a few pieces of brass and see what happens. I think rcbs is the only ones that make small base dies labled as such.

If you don't like the lake city stuff send it to me i can make it fit my rifles.

[EMgun08]

I second earl39's comments. I received some LC 07 brass from a friend that was shot thought a M240 and it needed to be small based sized, then full length and finally trimmed to length before it would fit in my chamber. Removing the crimp from the primmer cup was the final step in the process.

[stangfish]

I second earl39's comments. I received some LC 07 brass from a friend that was shot thought a M240 and it needed to be small based sized, then full length and finally trimmed to length before it would fit in my chamber. Removing the crimp from the primmer cup was the final step in the process.


Yep, That I forgot. You could try the RCBS. Send me a handfull and I will run them through the Small base die and send them back to you.