Gunsmithing 7mm saum free bore

BusterB

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Minuteman
Oct 31, 2011
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Bristol, VA
Building 7mm saum to run in short action with accurate mags with 180 berger hybrids (and possibly 195 when available) what freebore should I order for the reamer?

Thanks

Sent from my SCH-I605 using Tapatalk
 
Building 7mm saum to run in short action with accurate mags with 180 berger hybrids (and possibly 195 when available) what freebore should I order for the reamer?

Thanks

Sent from my SCH-I605 using Tapatalk

My reamer designed specifically for the 180 Hybrid and Accurate mags has a freebore of .037" and 2.100" bolt face to throat measurement. The OAL is ~2.950". The OAL with trimmed and tipped bullet's is slightly shorter. I have heard but not confirmed others are using ~.040" freebore as well.
 
Building 7mm saum to run in short action with accurate mags with 180 berger hybrids (and possibly 195 when available) what freebore should I order for the reamer?

Thanks

Sent from my SCH-I605 using Tapatalk
My reamer for my saum SA pushing 180 hybrids 0.56 this giving me 2.965 touching land so my OAL im using 2.955 on accu mag.(max OAL 2.970)
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My reamer for my saum SA pushing 180 hybrids 0.56 this giving me 2.965 touching land so my OAL im using 2.955 on accu mag.(max OAL 2.970)

bjay that would be .056" lead and a .040" throat (freebore) with a 2.101" bolt face to throat.
 
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bjay that would be .056" lead and a .040" throat with a 2.101" bolt face to throat.

You are right.. i also told robert my specific oal length.. i do beleive this reamer is short..he mention he has individual throat reamer he can adjust the depth of throat..i figured i can use accu mag to my max oal and still clear magazine.
 
So you think he moved the throat out a touch for you with a throat reamer? That might make sense since his reamer is virtually the same as mine (only .003" difference). I ended up right where I wanted with ~.025" extra to chase lands. I have a throater as well if I wanted to move it out a bit.
 
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So you think he moved the throat out a touch for you with a throat reamer? That might make sense since his reamer is virtually the same as mine (only .003" difference). I ended up right where I wanted with ~.025" extra to chase lands. I have a throater as well if I wanted to move it out a bit.

Im sure he did coz he told me his reamers are ordered short throated and when i told him the oal chased land i wanted he said not a problem ill stop the cut wherever oal you desire..im positive he has throater on ever caliber thats why his reamers are all short..make sense to me:)
 
Building 7mm saum to run in short action with accurate mags with 180 berger hybrids (and possibly 195 when available) what freebore should I order for the reamer?

Thanks

Sent from my SCH-I605 using Tapatalk

Make a dummy to your desired OAL and let either PTG or JGS measure the free bore and grind the reamer accordingly.