375 Ruger sizing problem

[Varmint Hunter]

I've been reloading for my 375 Ruger Guide Gun for awhile. Reloads shoot very well with occasional groups under an inch at 200yds.
Yesterday I noticed that it took a bit more pressure on the bolt handle then it should take to close the bolt. All the reloads shot well but the tight bolt closing has my attention.
Here is what I found today:
New brass measures 2.055" from the base to the datum line on the shoulder
Brass fired 4x measured 2.059"
My sized and reloaded brass measured 2.058"
All of the brass was about .007" short of max length

I re-adjusted the FL sizing die so that the brass measured 2.056" but the brass was actually tighter in the chamber.
FWIW - I'm currently loading Nosler 260 Accubonds but the brass is tight even before loading.

Anyone have an idea what's causing the problem?

 

[AZShooter]

Have you tried sizing the brass with the FL die even closer to shell holder than last sizing? Sometimes in moving the shoulder rearward the case sides will bulge making it tight. It might require a bit more sizing.

It would help if you covered a sized case with a sharpie, chamber it and look for rubbed off areas of chamber contact.

 

[Dean2]

Have you tried sizing the brass with the FL die even closer to shell holder than last sizing? Sometimes in moving the shoulder rearward the case sides will bulge making it tight. It might require a bit more sizing.

It would help if you covered a sized case with a sharpie, chamber it and look for rubbed off areas of chamber contact.

He is using a FL die and has already screwed it down further, that is what is causing the brass to be even tighter in the chamber.

To the OP, there are potentially a few issues that could be causing this. Is this happening loading empty but newly primed brass, or are they complete reloads? Only way to know for sure what the issue is, is to figure out exactly what part of the brass is binding, that will tell you what the fix is.

In order I would think most likely given your description, top of case binding on chamber. The comment about getting worse as you bump the shoulder back which also sizes the body more makes me suspect this. To check trim a case .005 changing nothing else, and try the fit again. Next most likely since this is not a belted case is expansion just above the web that isn't being fully removed with the amount you are sizing the brass.

 

[AZShooter]

Like I said continue to move die towards shell holder and size again. Repeat till you are camming over the press. If it still won't fit report back.

 

[Varmint Hunter]

Like I said continue to move die towards shell holder and size again. Repeat till you are camming over the press. If it still won't fit report back.

I'll give it a try but suspect that I'll begin to see excess headspace by lowering the FL die further.
The sharpie idea is a good one. - Thanks