Need Help - 7SAUM 180gr Hybrid Freebore

thewakler

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Joined
Apr 28, 2019
Messages
8
Location
MIL
Hi all, I'm currently stationed overseas and looking to get an order for a 7SAUM (Short Action) placed so it's ready when I get back next year. This rifle will be a 80% hunting rifle up to elk, and 20% LR out to 1500+. I'm trying to determine what freebore I should get. From looking at previous threads, it seems the .188fb works well for this round at the 2.95 COAL limit. I'm mainly interested in shooting the 180gr Hybrid, but could also envision the 168gr LRX or 175gr ELD-X.

1. Are more people running the sammi .090fb or .188fb? For those with the .188, how far off the lands are you with a 2.95 COAL?

2. Could someone confirm the CBTO measurement of a 2.95 COAL 180 Hybrid? I'm getting 2.191 CBTO with sammi brass specs. (Berger listed .768 BTO, 1.527 OAL, sammi 2.035 CL)

3. Does anyone have a junk sammi piece of brass they'd be willing to load up a dummy round with a 180 hybrid? I'll buy.
 

BUSTINDOGS

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Jun 19, 2012
Messages
268
Location
Minnesota
I have a 7mm SAUM with the sammi standard chamber. With that the 180 hybrid is longer than 2.95 when touching the lands.

I have a piece of 7 saum on my bench with a 180 in it if you want it.
 

thewakler

Member
Joined
Apr 28, 2019
Messages
8
Location
MIL
I have a 7mm SAUM with the sammi standard chamber. With that the 180 hybrid is longer than 2.95 when touching the lands.

I have a piece of 7 saum on my bench with a 180 in it if you want it.

Do you know how far off the lands you're at with 2.95?

Pm'd you about the dummy round.
 

BUSTINDOGS

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Jun 19, 2012
Messages
268
Location
Minnesota
Base to o-give with the 180 hybrid is 2.230 with a Hornady comparator at an over all length of 2.950 of course this will very as hollow point bullets are not consistent. A base to o-give of 2.226 is what I was shooting for best accuracy. That would be about a .032 jump with my rifle with about 500 rounds threw it.
 

arb5087

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Joined
Jul 20, 2021
Messages
11
Location
PA
Go with the .188 free bore, I have run 180 eldm thru my tl3 bighorn and XLR chassis with aics mags fits the mags perfectly. I have not run the bergers yet. I am around .020" off the lands.
 
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