How much sizing at shoulder diameter?

[gsxr1k]

I have a 6.5 tcu. My brass comes from the chamber at .371 shoulder diameter. My brand x full length die sizes the shoulder to .367. My brand Y sizes it all the way to .364. It takes alot of lube and effort to use brand y die and I feel that's excessive sizing. Am I correct on this and how much shoulder diameter reduction is appropriate?

 

[JFrank]

.002 is preferred

 

[KMart]

If brand x sizes your cases so that there is no problem chambering the loaded case, that is the one I would use. There is no need to reduce the dimensions of a case more than you have to.

 

[dgeesaman]

Definitely not the brand x die. The brand y die isn’t ideal either.

If you want to get the most from your brass I’d get a custom die. But that may be overkill.

 

[gsxr1k]

Thanks for the replies. I felt that .002 to .003 would be enough as well. No problems chambering. Btw Brand x is an RCBS die and Brand Y is a Redding bushing die. I couldn't believe a Redding die would reduce the shoulder diameter that much. I sent it to Redding and they said it was within their specs.

 

[dmoran]

@gsxr1k
IME, your "X" die sizing them 0.004" is not bad.
Myself want at least 0.002" minimum (only 0.001" per side clearance) with 0.004" being about maximum.
Ideally 0.0025" to 0.003" is a perfect amount IMO, but would not be upset at 0.004" either.
Good Luck

 

[gsxr1k]

@gsxr1k
IME, your "X" die sizing them 0.004" is not bad.
Myself want at least 0.002" minimum (only 0.001" per side clearance) with 0.004" being about maximum.
Ideally 0.0025" to 0.003" is a perfect amount IMO, but would not be upset at 0.004" either.
Good Luck

Thank you. I was thinking the same. I was feeling that the .008 from the Redding die is way too much. The effort to size one is what made me check it. I sent it to them. They said it's in spec at .008 reduction and sent it back. I wont use it like that. I'll make a neck die out of it

 

[KMart]

I have a 6.5 tcu. My brass comes from the chamber at .371 shoulder diameter. My brand x full length die sizes the shoulder to .367. My brand Y sizes it all the way to .364. It takes alot of lube and effort to use brand y die and I feel that's excessive sizing. Am I correct on this and how much shoulder diameter reduction is appropriate?

Just curious. At this die setting using the x die, how much is the shoulder set back, cartridge base to shoulder datum, from the fired case dimension?

 

[243winxb]

Brand Y is a Redding bushing die.

I compared same in 243 Win. Results same.

The Redding Fl bushing die has extra clearance so the unsized part of the neck can center the round in the chamber? Imo. I took measurement years ago, because the Redding Fl sized brass looked different then the RCBS Fl standard die at the body/shoulder junction.

Both dies allow rounds to chamber, when controling shoulder bump.

The Redding bushing die makes more accurate ammo for me.

 

[boltfluter]

I am amazed that Redding says .008 is within spec! I had a Redding .22BR die years ago that would wrinkle the shoulders from excessive body sizing. Sent it back with a few fired cases and they sent me a different die that worked great. Sounds like things may have changed at Redding. Too bad.

Paul