GAP-10 "Finicky chamber"?

[EasternNChunter]

I am at work but I think the dies I ordered are the Redding Type S Bushing die set. I can't remember which bushing I ordered but its the nitetride one. Again, going to be using Lapua brass, Reloader 15, 178 AMAXs, and Large Rifle Magnum primers. I already have lots of these primers and powder so I am at least hoping to use them. I also just got in 10 boxes of the 178 AMAXs.

 

[SWThomas]

I am at work but I think the dies I ordered are the Redding Type S Bushing die set. I can't remember which bushing I ordered but its the nitetride one. Again, going to be using Lapua brass, Reloader 15, 178 AMAXs, and Large Rifle Magnum primers. I already have lots of these primers and powder so I am at least hoping to use them. I also just got in 10 boxes of the 178 AMAXs.

Two flaws I see with the Redding bushing die: 1. If you go with smaller bushings you're not going to get any benefit from the expander ball as it will just stretch the neck back out. I asked Redding about this and they didn't have an answer other than to not use the ball. That's fine if you don't have any dents in the mouth. But auto loaders are notorious for denting case mouths. If you eliminate the ball you're going to have inconsistent neck tension, unless you turn the necks. I suppose you could try to polish the ball once you determine your desired neck tension.
2. Bushing dies aren't as concentric as one piece dies. The bushing has to have some radial clearance for ease of insertion and that thousandth or two of clearance will degrade concentricity. Not clamping the bushing down all the way will allow it to float a little, which can help a little.

 

[EasternNChunter]

Well, these are the same dies I have used in my Gradous and Dana English bolt rifles and all three shoot nice one hole groups.

 

[SWThomas]

Well, these are the same dies I have used in my Gradous and Dana English bolt rifles and all three shoot nice one hole groups.

Cool! I'm glad they work.