308 win sizing issue

[Rosamond]

So my problem is that I reloaded a couple hundred rounds of 308 using LC and 70's vintage L2A2 brass. I used full length RCBS dies and trimmed by the book. They chambered and shot just fine out of the M1a they were originally fired out of, but will not chamber in my LR 308. I no longer have the M1a any suggestions or tips?

[highpower790]

A small base die might work,the chamber could be a little tight.

[bcrich]

I bet the shoulders need to be bumped a bit further !

[NiMiK]

I bet the shoulders need to be bumped a bit further !

^^ this


Sent from my iPad using Tapatalk

[Rosamond]

I use a Rock chucker and when I set up my die I adjust it till it touches the shell holder. Is there there something else I can do? It feels like really tough brass.

[highpower790]

I use a Rock chucker and when I set up my die I adjust it till it touches the shell holder. Is there there something else I can do? It feels like really tough brass.

When shell holder touches die ,back off on ram,then lower die 1/8-1/4 turn

.

[J-cat]

Cam over

[Rosamond]

I will give it a try. Thanks!

[OpenSightsOnly]

use imperial sizing wax for case lube

for neck lube use mica/graphite

[74c5]

You can always get a second shell holder and grind 0.005 to .015 off of the top of it. That will move the die farther down on each piece of brass. Naturally, start with a lower number and work your way further down the holder. Having the extra shell holder lets you go back to original or, a lesser grind.

[liber]

So my problem is that I reloaded a couple hundred rounds of 308 using LC and 70's vintage L2A2 brass. I used full length RCBS dies and trimmed by the book. They chambered and shot just fine out of the M1a they were originally fired out of, but will not chamber in my LR 308. I no longer have the M1a any suggestions or tips?

Using a case gauge should show that the head is sticking above the gauge on the head side of the gauge, if the shoulder is too high.

[JMP]

Normal FL sizing should do the trick. If you try everything and it still doesn't go, cover the piece of brass with a black Sharpie marker. Then slowly feed it in and see where the contact point(s) is(are). That should give you some clues. Most dies when set to the full cam over position actually over-size for the average factory chamber. That's why it's best to have a professionally installed chamber. Trimming is rarely the solution as most people get a little trim happy in my opinion.

Make sure your die says FL on it and isn't a neck only. I've not had much luck using case gauges as I usually use tight chambers that fit right in a case gauge even after firing.

[Victor Cachat]

I thought my shoulders needed bumping when my .308 reloads were not seating, but a small base die set was the fix.

[liber]

They chambered and shot just fine out of the M1a they were originally fired out of, but will not chamber in my LR 308.

I use a Rock chucker and when I set up my die I adjust it till it touches the shell holder. Is there there something else I can do? It feels like really tough brass.

I've not had much luck using case gauges as I usually use tight chambers that fit right in a case gauge even after firing.

Just to point out they were fired out of an M1A and the OP has an LR-308, I suspect there's a good chance the case would fit in a case gauge.

Could also use a headspace gauge. I just thought it would be easier and might be more accessible for him to check with a case gauge.

Per his second quote it's not clear how exactly the case is fitting in the sizing die. Definitely the shoulder would be in question at this point.

Even using the 40 cal method of getting the headspace would be of help.

[fguffey]

I use a Rock chucker and when I set up my die I adjust it till it touches the shell holder. Is there there something else I can do? It feels like really tough brass.

Is there something else

Yes! A reloader can determine if the case won or the press won. Brass has resistance to sizing, there is a chance the case has more resistance to sizing than the press can overcome. There are times the case lube being used is the difference. I use a no-name lube, I have store bought case lube, I use it on cases that have little resistance to sizing.

To determine if the case won or the press won measure the gap between the bottom of the die and top of the shell holder before lowering the ram with a feeler gage, I know some use light, others make wild guestimates, I use a feeler gage. If the case does not get forced into the full length sizing die the case will not make it to the shell holder. It is possible to remove the die from the Rock Chucker before lowering the ram. To remove the die with the case rotate the shell holder to remove it from the ram and case at the same time.

Then someone should ask 'WHY?: Removing the die with the protruding case allows a reloader to measure case head protrusion from the die. If the case got sized when the ram was raised the case head protrusion should be .125" 'because' the shell holder has a deck height of .125".

When forming cases for short chamber I use a feeler gage between the deck of the shell holder and case head to increase the dies ability to reduce the length of the case from the shoulder of the case to the case head. RCBS shell holders allow for a .012" thick feeler gage +/- a few. AND! adding the feeler gage increases the presses ability to overcome the case's ability to resist sizing.

Then there is deterring the die and shell holder's ability to return a case to minimum length.

F. Guffey