Hello gang-

I'm enjoying a Maynard No. 16 which came to me wearing a barrel rechambered to .25-20 WCF. My cast bullets are oversized at .262". Given the scarcity of brass (I have just one box of Winchester), I prefer to load the cases without resizing, but brass fired in this chamber has necks too large in I.D. to give even a loose slip fit on those .262" bullets. 

I ordered a Redding neck sizing die, but it works the neck far more than I am comfortable with. 

So here's my question: I see there are .32-20 Starline cases on GB which have been formed to .25-20. Are the necks of the Starline cases thicker than the notoriously thin Winchester brass? Anyone happened to use some of these? My thought is that thicker case neck walls might give me just enough smaller I.D. to give my cast bullets a tolerable fit. 

I appreciate any experience you care to share! 

Well, that’s the other approach I will have to take, is to make a neck sizing die to the desired dimensions. I just thought the Starline brass - if thicker - would solve this problem and give me some more cases. 

Yes, the bullet as cast is oversized, but I prefer to shoot them as cast and usually see good results. Perhaps I’ll be proven wrong this time… 

Thanks for the input!

That is both bore and groove diameter, as large a bullet you are going to use.

Oleblacksmith wrote on Sep 9^th, 2025 at 7:58pm:


Different .25-20…..

Gents-

Thank you for the information and good suggestions. I'm going to order some of the Starline cases and see if they offer any improvement.

If they don't, I'll spin up the lathe and make a neck sizing die to massage the case necks as lightly as possible.

My Winchester brass measures .007". A friend checked a piece of Starline .32-20 sized down to .25-20, and read .009" neck wall. 

As I said, I'm going to order 100 cases. Hopefully, they will improve the bullet fit in a fired case, but regardless, I'd like to have more than my current 50 cases.