7mm SAUM Build Help

[R_Swanson]

Hello everyone. New guy here, although I have read this forum and used it as a resource for a while now.

I am building a switch barrel T3x for long range hunting - and getting into reloading at the same time. Actually decided on this project just before covid, and then everything hit the fan so I hoped to wait it out - thats not realistic at this point, I have an elk hunt in the fall of 22 I want this gun for it. I've parted together most of the reloading equipment and most of the build to get this going. I havent ordered the 7 SAUM barrel yet.

Build:
Tikka T3x with long action bold stop - I have both magnum and .473 bolt face bolts.
Manners EH1 Tikka with bottom metal
Bushnell LRHSi 4.5-18
Using a stock CTR barrel in 6.5cm for deer/antelope - want the 7mm SAUM for anything larger (or muleys if I feel like it, etc). The 6.5 barrel from Tikka has been very accurate for me and has tons of life left, I prefer not to discard it, hence the 6.5CM. I realize there are better cartridges (in theory) for this purpose.
Want to go with a Carbon barrel for the SAUM, leaning towards 24" so I can run it with my Ultra 7 - but open to suggestions. Also leaning towards 1:8 twist, but open to suggestions.

I want to load the SAUM long and run heavier bullets, preferably the longer Bergers. This is a two part question:
- Can I just spec an extended freebore from the barrel manufacturer, or is there more to it? Some CF Barrel manufacturers that offer shouldered prefits for Tikka's (like Carbonsix aka McGowen) require 3-4 dummy rounds built up for the to do this. Well, I don't have dummy rounds, as I haven't build the gun yet or reloaded for it.
- I have seen a lot of different freebore's quoted on here and SH for this round. Is there a general go-to for this round and the longer bullets, or is that not really how it works?


Sorry for the long post - and thanks for any assistance.

 

[martinakl]

You'll need a 2nd bolt for the larger case. Creedmoor and SAUM are not the same.
Check out JA Outdoors. He sells bolts. @North Idaho Hunter on here.

I'd reach out to Hells Canyon Armory for a carbon barrel. They have the freebore figured out for the 7mm SAUM and make a fine carbon barrel. They seem to have Tikka barrels nailed down.

Online Store | Hells Canyon Armory

www.hellscanyonarmory.com

 

[R_Swanson]

You'll need a 2nd bolt for the larger case. Creedmoor and SAUM are not the same.
Check out JA Outdoors. He sells bolts. @North Idaho Hunter on here.

I'd reach out to Hells Canyon Armory for a carbon barrel. They have the freebore figured out for the 7mm SAUM and make a fine carbon barrel.

I have a magnum bolt face. The donor gun was a 300WSM... The CTR I discussed is now wearing a 6mm CM. Good call though, I will update the OP since I never said that and its confusing.

Thanks for the suggestion on Hells Canyon! I havent looked into them much.

 

[Kimber7man]

Can I just spec an extended freebore from the barrel manufacturer, or is there more to it? Some CF Barrel manufacturers that offer shouldered prefits for Tikka's (like Carbonsix aka McGowen) require 3-4 dummy rounds built up for the to do this. Well, I don't have dummy rounds, as I haven't build the gun yet or reloaded for it.

The reason they ask for 3-4 dummy rounds is so they can build your rifle by throating it correctly, for the specific bullet at the specific COAL you want it at. That's the beauty of building a custom rifle, you build it around what you want, rather then "getting what you get"…

 

[Ucsdryder]

I would strongly suggest a 20" barrel. I run mine with 180eldm which are about the longest you can get. Once you buy the brass and bullets then seat some dummy rounds without primers or powder, end of the bearing surface at the neck/shoulder junction and send it off!

 

[R_Swanson]

The reason they ask for 3-4 dummy rounds is so they can build your rifle by throating it correctly, for the specific bullet at the specific COAL you want it at. That's the beauty of building a custom rifle, you build it around what you want, rather then "getting what you get"…

What if the bullet you want to shoot doesn't end up shooting as well out of your barrel, and you need to switch?

Please correct me if I'm wrong, but if I am understanding this correctly: Say I load for the Berger 195s, which I think are the longest thing out there. If I end up wanting to shoot 180's, I'll be looking at a lot more jump if the person I get the barrel from reams my barrel for the 195s, right?

Seems like there's a lot of variables... To be honest I can't tell if I'm making this overly complicated or this is what I should be considering before spec'ing the barrel.

Sorry for the noob questions, I appreciate the help.

 

[R_Swanson]

I would strongly suggest a 20" barrel. I run mine with 180eldm which are about the longest you can get. Once you buy the brass and bullets then seat some dummy rounds without primers or powder, end of the bearing surface at the neck/shoulder junction and send it off!

Thanks for the reply, forgot to quote you, but same question as I posted above.

 

[Ucsdryder]

Thanks for the reply, forgot to quote you, but same question as I posted above.

195 is A LOT of bullet for that gun. I'd be shocked if you can run them in your Saum. The 180 Berger are similar, slightly shorter bearing service. Go with your best bet then adjust from there.

 

[R_Swanson]

195 is A LOT of bullet for that gun. I'd be shocked if you can run them in your Saum. The 180 Berger are similar, slightly shorter bearing service. Go with your best bet then adjust from there.

Can you expound? I'm ignorant as to why.

 

[Ucsdryder]

7 Saum is a great round. In my opinion the best hunting cartridge out there! But it's not a barn burner. The 195s are great for the powerhouse calibers like the 28nosler. The sweet spot for the Saum is the 160-180gr.

 

[R_Swanson]

7 Saum is a great round. In my opinion the best hunting cartridge out there! But it's not a barn burner. The 195s are great for the powerhouse calibers like the 28nosler. The sweet spot for the Saum is the 160-180gr.

Gotcha - so your point is I wont get the velocities out of the 195's I'll be looking for. Much appreciated. And thanks again for dealing with the beginner questions - I know it can be annoying, but sometimes after doing so much reading/research your head hurts - it just helps to ask some dumb questions that you arent putting together on your own, haha!

 

[Ucsdryder]

My 20" Saum is getting 2750 with 180eldms. I wouldn't want to go any slower and I wouldn't want a barrel any longer.

 

[Kimber7man]

Agree with @Ucsdryder, the 195 is a lot for the 7SAUM but it can be done. likely with a long action and a longer barrel to help with velocity.

FWIW I'm using the Berger 175 elite out of my 22" 7SAUM at close to 2,800, loaded at 2.99" COAL.
Have some 180 hybrids to try as well.

 

[Kimber7man]

What if the bullet you want to shoot doesn't end up shooting as well out of your barrel, and you need to switch?

Please correct me if I'm wrong, but if I am understanding this correctly: Say I load for the Berger 195s, which I think are the longest thing out there. If I end up wanting to shoot 180's, I'll be looking at a lot more jump if the person I get the barrel from reams my barrel for the 195s, right?

Seems like there's a lot of variables... To be honest I can't tell if I'm making this overly complicated or this is what I should be considering before spec'ing the barrel.

Sorry for the noob questions, I appreciate the help.

Correct on the "if the bullet doesn't shoot"! The hybrid design is less sensitive to seating depth, which is a benefit.