Enlarging case neck size

Dr. Vette

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I've got some once fired 7mm brass that the seller was "nice enough" to run though his die before selling the brass. Yes, the primers are gone but now the necks are sized smaller than I'd like as well. Generally I've been using a Redding bushing die for this caliber, but the necks on these pieces are small enough that the bushing doesn't even touch them. Checking wall thickness shows that the brass is no thinner than normal, just sized smaller.

I've tried using my Lee collet die just to expand the necks a bit using the center expander without applying external pressure to the necks, but they're still too small.

Other than loading them as "sight in loads" or similar and then firing them in my rifle is there any easy way to enlarge the necks slightly so that I can size them with the bushing die?

Thanks for any suggestions you may have.
 
"Other than loading them as "sight in loads" or similar and then firing them in my rifle is there any easy way to enlarge the necks slightly so that I can size them with the bushing die?"

Well, you could try seating bullets and pulling them. But, if your only goal is ti use your bushing die I think you're agonizing over a moot issue.
 
You could use a neck turning mandrel on them. The turning mandrel or the expanding mandrel, whichever would give you the proper dimensions. Sinclair and others make dies for mandrels.
 
Try them as they are. I find that the lee collet die works great on my 7mm. The collet may not be the size you like ,but as far as accuracy I've had great results in many cartridges using the lee collet .
You may be pleasantly surprised by the results.
If not you can always use a larger expander mandrel and then resize with your bushing dies.
If you don't have a larger mandrel you can use a tapered punch and push it into the case mouth to open it up a bit. I've tried both and they both worked well.
 
I'm not agonizing over anything - just wondering if there is a simple way I hadn't thought of using.

I don't have any larger mandrels, and for now I'll probably use the collet die on them. However, I'll now have to keep track of which loads are sized in which manner so I can see if it makes any difference - good or bad.

Thanks for the tips.
 
If you have a 'standard' die with a 'normal' expander, run the expander through.

Collet sizing them may not open them as far as you are used to but they will be uniform.

Using a pre-turning expander then bushing sizing will work but works the brass one extra time.

Or

Load em and try em. If they shoot the same, forgedaboudit!
 
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