I have a Blaser R8 rifle in .338 win mag. This rifle(barrel) was a special order because I wanted a 1:10 twist so they used one of their .338 Lapua barrels and chambered it in .338 win mag.
For whatever reason, the chamber is quite large, I’d bet that it is within SAAMI tolerances but for the first time in over 15 years reloading over a dozen different belted magnum cartridges, I have had to use a special collet body die, otherwise the cases, best “case” scenario; get shaved above the belt, or stick in the die. So I have to run them through this annoying body collet die, then FL size. And the instructions with the special die suggest you do it the other way around, which makes absolutely no sense.
When I spoke to Blaser they said the solution is to just buy their factory ammo…Because they don’t recommend reloading.
So would it be worthwhile, in terms of accuracy, but above all, would it do away with this problem of having to resize with a collet around the body in a separate step, if I got some custom dies made?
The one company I spoke with told me they would need three cases that had been fired three times, neck sized only, but left unsized after last firing. After checking their email, they said it would also take care of the problem.
Now, I can’t get a neck size die for less than around $80, (here in Italy) and I’d never use it again.
The cases won’t run though the FL die at all without shaving the edges, I already tried adjusting them for a minimal resize but it just won’r work.
So the only option I can think of, and it calls for Bubba Engineering, is to use my grip n pull www.grip-n-pull.com to squeeze the neck just enough to hold the bullet and fire away. I’m not looking for accuracy, so It “should” work ok, right?
I have some Norma brass which is very soft, so it should fit the bill nicely.
Sound like a plan?

Sure, it's a plan. Anything that will provide enough neck tension will create a "reloadable" case. I'd hate to think what your runnout might be, or how inconsistent your neck tension, but cases reloaded in such a way will definitely go "bang" and the bullet will travel downrange. Just how consistently it will travel downrange is a matter of speculation until you try it.

It sounds as if your FL die is shaving the (overexpanded) cases near the base. If so, have you thought of simply reaming the FL die a bit larger near the base? Something like you would inside chamfer a case mouth (but of course the die material is much harder and the opening much wider. If you could find a ball-shaped or cone-shaped stone of the right sized to chuck in a drill you might be able to alleviate your problem and go back to utilizing your FL die (but now as a "partial full length" die).

Oversized chambers for belted magnums have been a problem for as long as they have existed. Manufacturers take advantage of the ability of the belted case to headspace on the belt by making their reamers considerably oversized. If you start out with an oversized reamer you can make many more chambers with it before it wears to the point that the chambers are no longer large enough.

Hey, I just noticed that the grip-in-pull sells for $39.95. For less than that you can buy a Lee Collet neck sizing die. This die will touch only the neck, so it matters not (within reason) how large the base of your fired cartridge. The Lee Collet die requires no lubrication and is quick and simple to use. You can also vary (increase) the amount of neck tension by honing the mandrel down by .001 or .002" if you desire.

I use Lee Collet dies for virtually all of my bottlenecked cartridges and find them both much handier than conventional dies (no lube to apply or remove) and they also make "straighter" ammunition.

Much cheaper, and not hard, would be to polish your dies out with some emory paper, in a lathe is best.
Reaming a Fl die is impossible unless you anneal it first, and then you have to have a reamer, not cheap.
I, always looking for the lowest cost way to do it myself, would chuck it up and polish until it sized cases I liked.

Problem is with the gun and a poor chamber. I would send it back pronto..

You can send RCBS or whoever three fired cartridges and get a set of custom dies made, but the wait will be long and costly..

Option no. 2 is send the dies and three fired cases to Dennis Olson.He can soften recut the dies and harden them. He charged me $27. for my 9.3x62 dies cut to .375 x 62..

Option no 3 is to continue what you are doing, its a lot of trouble but its working. Probably overworking your brass also, so case life will no doubt suffer greatly, unless you anneal before each reloading.

Since you are in Italy, I doubt if you will be sending your dies around the world for modifying; I would do what I said above. It could be your die is small, not the chamber is too big; one way to find out; cerrosafe cast molds of them and measure. But it doesn't matter, it is easy to fix a sizing die to match a chamber.

I dont suppose it will do too much hard to try and polish the die out, so I'll try it.

Stonecreek, I already have the grip n pull, and there are no Lee collet neck dies around at the moment here. Also these cartridges just need to be fired and neck sized, where the bullets goes doen't matter.

I'll second Ray and point the finger at a bad chamber. I own 3 R93's which I treat/size as follows :

- .222 Rem : collet neck sizing with Redding Comp' dies + an occasional shoulder bump in the body die ;

- .300 Win Mag : regular Hornady dies and partial sizing (= sizing adjusted for my Rem Sendero in same caliber ;

- 9,3x62 : regular RCBS dies and partial sizing.

I never had any problem with the above and the only cases I lost after <10 reloads came from split necks...

Everyone is quick to point out the problem before any actual diagnostics are done. It's like sawing off the chair leg before you determine that it's too long. It could be the chamber, the dies, or the brass, or a combination. Chamber? It should meet CIP dimensions and only a chamber cast will tell you that. Brass and dies need to be compatible with the chamber. Remember we are dealing with products manufactured in at least 3 different countries and to a fairly wide margin of allowable tolerances. No one can be sure of anything without some measurements. But to fix the issue, without more drams, making the sizing die larger to accommodate the chamber/brass relationship is a viable option. And it is free. Personally, I would try a different make of die first. It might be too small, on the low end of the tolerance spectrum.

dpcd, wise words.

Of course I will try modifying the die first.