have to seat bullets below saami to chamber

[garsticker]

I installed a mcgowen prefit on my savage and used a go-no gauge to set headspace
I set it to as minimum as I thought safe...now when I loaded my bullets I have to set at or under .(.0025)saami for the bolt to close...is my headspace too tight or what...it is a 6.5x284 if that makes a difference...

 

[Lefty7mmstw]

My brother has a factory ruger in 300 h@h that is often under saami; depending on the bullet nose profile of course.

The long throat thing seems to be more of a remmy thing than anyone else. Most of my( non rem 700) pipes aren't that much over with the bullets seated close. I seat to fit my mags though, so it isn't of that much importance to me as long as she groups and she's safe.

Shoot her a few hundred rounds and she'll grow. If you can't stand it have a 'smith lengthen the throat a bit.

 

[garsticker]

is there a pressure danger

 

[Lefty7mmstw]

is there a pressure danger

Not as long as you work up your loads. You don't have a big enough caliber to require any real freebore.

 

[RT2506]

Seating depth is a relative thing. The saami depth is just a depth that should work with that particular bullet used in the data in any factory action and chamber rifle. When you get into custom cut chambers things can be different. You did not mention what bullet you are using so we can't really tell if your throat is really short or you are using a really long bullet like the Berger VLD. What twist is your barrel? If it is a 9" twist then your throat was probably cut to use 130 gr bullets as the heaviest. You need an 8" twist to shoot most 140 gr bullets. Head space of the chamber has nothing to do with seating depth of the bullet. If you head spaced using the go gauge and the bolt closed and the no go gauge and the bolt would not close then your head space is OK.

With any new barrel you will need to work up a NEW load for it. NEVER stick a round in a different rifle or barrel that you were shooting in something else. Always back off the powder and work back up. Yes, if you are jamming a bullet into the lands there could be pressure problems. I would suggest that you back your bullet off the lands 10 thousands and use a starting load of powder and work up in half grains to find the velocity you want and relative accuracy then start playing with seating depth to dial in the accuracy.

 

[garsticker]

I've used 130gr. Accubonds 140gr. Bergers.123gr. Amaxs and 140gr. Amax..1-8 twist...i am used to seating bullets out to the lands in my 700 Snyder custom...i was just concerned about the length being that short...never had this happen before...i never jam a bullet in once I feel the resistance in the bolt I take the round out..i usually keep it just a few thousandths off lands..but this barrel is causing the bullets to be seated under saaami specs with the bullet a few thousandths off lands

 

[RT2506]

I've used 130gr. Accubonds 140gr. Bergers.123gr. Amaxs and 140gr. Amax..1-8 twist...i am used to seating bullets out to the lands in my 700 Snyder custom...i was just concerned about the length being that short...never had this happen before...i never jam a bullet in once I feel the resistance in the bolt I take the round out..i usually keep it just a few thousandths off lands..but this barrel is causing the bullets to be seated under saaami specs with the bullet a few thousandths off lands

Sounds like you just have a very short throat in that barrel. A smith can lengthen the throat for you. Most of the time the saami seating depth is well short of the lands in most barrels. I would call Mcgowen and tell them your problem. Maybe they will deepen the throat for you. They should do it for nothing as much as their barrels cost.

 

[flashhole]

+1 what RT said.

 

[boomtube]

SAAMI Specs are for manufactors and gunsmiths, one of the reasons for handloading is to custom make ammo that works best in our own rig. Headspace, as such, is easily compensated for if the handloader knows what he's doing. Setting your rifle's chamber headspace at or shorter than "minimum" won't affect safety but it may prevent proper chambering of your ammo.

Headspace has nothing to do with OAL/seating depth. Seating 2.5 thou under standard OAL is meaningless and SAAMI only sets the max cartridge length and that's mostly for magazines and feeding anyway, a freebored throat can easily be much longer than minimum.