Case web support - Savage small shank

[moxford]

Hi all,

Just got a barrel back which was supposed to be a Savage small-shank tenon. The max spec for the amount of "go gauge stick out" off the barrel is 0.128 - 0.130 from other forums, but I cannot find anything official.

Protrusion on this particular barrel (30 sherman magnum, same case as 300 PRC) is at 0.150, so it will have 0.020 more unsupported case around the web if I just set the barrel forward the same amount.

Does anyone know the "official" spec? Is it actually 0.128-130?
For 30SM/300 PRC, am I just being obnoxious and the 0.020 doesn't matter? Really would like to avoid damaging brass and/or having separations, but maybe 0.150 is technically out of spec for Savage small-shank, but completely fine otherwise.

Thanks!
-mox

 

[ARlife4me]

Hi all,

Just got a barrel back which was supposed to be a Savage small-shank tenon. The max spec for the amount of "go gauge stick out" off the barrel is 0.128 - 0.130 from other forums, but I cannot find anything official.

Protrusion on this particular barrel (30 sherman magnum, same case as 300 PRC) is at 0.150, so it will have 0.020 more unsupported case around the web if I just set the barrel forward the same amount.

Does anyone know the "official" spec? Is it actually 0.128-130?
For 30SM/300 PRC, am I just being obnoxious and the 0.020 doesn't matter? Really would like to avoid damaging brass and/or having separations, but maybe 0.150 is technically out of spec for Savage small-shank, but completely fine otherwise.

Thanks!
-mox

I have 2 new small shank barrel both from different makers. None are in either cartridge. Belted wm in 300 and 264 also have go and no go gauges for them. Not sure if I would be of any help?

 

[tobnpr]

^^^
Gauges are irrelevant here, not focused on headspace which can be fine with too much case exposed.


.125-.130 is typical spec.
.338 LM is .140-.145 because of a deeper boltface.

So, answer is "depends on"
Depth of boltface
Case web depth on the .300 PRC brass.
You need minimum depth of boltface plus .005-.010 clearance from the breech. Maximum is really determined by sectioning the brass- but .150 is not uncommon and I've seen more.