260 Lapua Brass problems** Problem solved!

Bingo, this had to have been the case. O well. Like other have said, I have put in an order to Peter for some new brass.

Thanks for all the help guys!

.296 nk .260 match finisher. I have used lapua and rem with no issues. I did have to turn if I was sizing up or down to make .260 brass

Just did some digging and it appears lapua brass is loading between .294-.296


If you have any problems that are related to the bbl I will help out at no charge. ;) Actually I can help with any problems you have at all. I hate to see someone discouraged when just starting.
 
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Sean built me a 260 recently. I am using new lapua 260 brass with no prep with no problems (only 25 rounds through it since I don't shoot that much in the winter) so far.

With 139 gr Scenar's in lapua brand new brass with nothing done to them except loading my loaded round has a neck exterior width of .2935 to .2940. A once fired round that has an over exterior neck diameter of .2945 to .2950. A brand new lapua case measures an exterior neck diameter of .2900.
 
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260 Rem SAAMI spec. neck dia. is .299 on the reamer.
You must have .003 or more clearence between the loaded round and chamber to avoid creating excessive pressure from too tight a neck.
Mick
 
Can you accurately measure a loaded round and see what it mics to on the neck?

Okay so I grabbed a subset of 10 rounds in hopes of getting some of the tight ones and maybe some of the ones that fed and extracted well.

Here are the loaded neck diameters:
0.293, 0.293, 0.2935, 0.293, 0.2935, 0.2935, 0.294, 0.294, 0.2935, 0.294


Here are their corresponding base diameters:
0.470, 0.470, 0.470, 0.469, 0.4695, 0.4695, 0.4705, 0.469, 0.469, 0.4695

Hope this helps.
 
Well A good friend of mine got a barrel from sean last year in 260 rem it wasnt stamped so we werent sure of the neck diameter but we assumed it must be saami spec.
Turns out after we installed the barrel and headspaced it used some fired brass my friend had FL sized them and they would not chamber
so he got some new brass but the necks had to be thinned they were to tight.

I dont remember for sure but it seems we had perhaps lead sluged the neck area of the chamber to get a measurement.

Imo you should contact sean and find out what neck diameter he is chambering the 260 in cause if it is the same reamer that chambered my friends barrel it is not saami spec.
On a side note once the brass was worked the gun shot very well.

I`ve never heard of a good smith not stamping his barrels` let alone multiple customer`s barrels. After reading this point, I would question the chambering job before anything else.
 
I have had similar problems with once fired Lapua 308 brass with the base not wanting to chamber. My two friends had the same problem with their coyote's in 308. We bought small base Redding 308 full sizing dies and now the brass works fine. I also bought a wilson case gauge so I could be sure I have the specs right on the brass (good peace of mind). The cost of these two items would be what a new box of lapua 260 brass is.

From what little I know, I would be more concerned about the primers falling out.

I recently decided I am only buying new brass and the best brass I can afford.
 
I read thru this quickly...like some have said...why buy junk used brass? Well, obviously that's a 50/50 coin toss just like buying a used barrel! Right? However, I think the biggest thing truly overlooked here is...just cause you have a 260 chamber by no means guarantees its gonna fire everyone elses fireformed 260 brass!!!! Or any other calibre obviously! If someone buys used brass and assuming it was a good purchase...you darn well better send a couple fired pieces to your smith when he is chambering and headspacing!!! I know...speeking form experience! My buddy was the beneficiar of 200 fireformed pieces of 6AI brass (I sold him my old barrel) and I was too stupid to remember to send a couple brass to my smith during rebarreling!
 
I have had similar problems with once fired Lapua 308 brass with the base not wanting to chamber. My two friends had the same problem with their coyote's in 308. We bought small base Redding 308 full sizing dies and now the brass works fine. I also bought a wilson case gauge so I could be sure I have the specs right on the brass (good peace of mind). The cost of these two items would be what a new box of lapua 260 brass is.

From what little I know, I would be more concerned about the primers falling out.

I recently decided I am only buying new brass and the best brass I can afford.

I would lean more toward this response. I see it all the time, guys can't chamber a round because their sizing die is not adjusted properly. I would get a small base sizing die and follow the instructions precisely while installing and see what happens. I'll bet your issue goes away. Or you could always scrap the brass and get a new batch.
 
Finally got all sorted out

Well the long and the short of the story was it was a problem with the brass. Peter at Hirsch Precision got me all set up with some brand new 260 Lapua brass in less than 5 days! Anyways, this new brass feeds and extracts perfectly and comparing the dimensions of the Old Lapua brass to this new stuff, it is no wonder it wouldn't feed. The base diameter was quite a bit larger which explained the shaving marks on the old stuff. I got all of my bullets and powder recovered from the old stuff and got some of my money back from the seller as a nice gesture. Needless to say I learned my lesson about brass and chambers. Also many thank to all of you nutters that offered assistance and in particular DG Photography and Sean at Northshore barrels who proved he stands behind his work even when it is off to a new owner.

Again many thanks!
 
Arcticcathonda.

If you still have that brass would you mind sending 1 or 2 pieced my way?

Just interested to do a test with them.

Let me know.
 
Well the long and the short of the story was it was a problem with the brass. Peter at Hirsch Precision got me all set up with some brand new 260 Lapua brass in less than 5 days! Anyways, this new brass feeds and extracts perfectly and comparing the dimensions of the Old Lapua brass to this new stuff, it is no wonder it wouldn't feed. The base diameter was quite a bit larger which explained the shaving marks on the old stuff. I got all of my bullets and powder recovered from the old stuff and got some of my money back from the seller as a nice gesture. Needless to say I learned my lesson about brass and chambers. Also many thank to all of you nutters that offered assistance and in particular DG Photography and Sean at Northshore barrels who proved he stands behind his work even when it is off to a new owner.

Again many thanks!

Good to hear you got it sorted out and dont overlook the fact that your chamber has been cut with a match reamer with a .296 NK you may have to turn the necks a bit in order to have the proper clearance.

Also others had suggested a small base die and that probably would have done it for you and you may still need one in the future once your new brass starts getting tight.
 
Some of that used brass is likely still good, as others have said the small base die would do it for you.. or as Boomer said, just try using a shaved down shell holder.. that way the case will get deeper into the die and form the base more. Perhaps try chucking the shell holder in a drill and grinding it on a stone.
I've had the same issue with the brass getting tight and shaving on the base when chambering. For me a redding body die does the trick.
 
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