Gunsmithing 7WSM build SA or LA?

[ugsly]

Ive done quite a bit of reading, some say SA some say LA. I would like to feed it out of a AICS style magazine and it needs to work. I will shoot 168-180gr bergers and will buy the reamer needed for the right FB. Thoughts?

Thanks guys,
Kc

 

[jbailey]

LA, especially if this is a WSM and not a SAUM. So much easier to find loads for. 180gr Berger is just too long to load in SA w/o pressure headaches. It can be done, but why not just deal w/ the 0.5" longer bolt pull?

 

[mcfred]

My 7WSM works fine in a Pierce SA M700 clone. To run the long Bergers you'll need a pretty short throat though.

Mine shoots 180 Sierras at 2850fps just fine with lots of case capacity remaining even with the stubby SMKs stuffed in the case a ways. It cycles fine, right, port-side up, or upside down from Alpha Industries mags. Shoots .3MOA at 200 yards. Better, if that 2.5" 3-shot group at 910 yards wasn't a fluke.

I don't see why you'd need a long action for a WSM. If you have a long action and you want every last bit form the 7mm bullets then there are bigger/faster cases for the 7mm.

 

[Cigarcop]

You said your gonna load them to shoot from the AICS mag so your FB will be on the short side def putting the BT portion below your neck / shoulder junction and into the case.... If you throat it long depending on the action in a SA they
might not eject a loaded round.

 

[knockemdown]

If you go SA 7WSM, heed the above & focus on running 168s or smaller. I've run 180s from my SA 7WSM, but the velocity performance is not there with so much boolit infringing on capacity . Been happily running a mild load (2970fps) with 162Amaxs from Alpha WSM mags. GAP short throated my stick, accordingly.

If you are deadset on 180s, a LA would be the better mousetrap...

 

[ugsly]

Are you guys running them outa a 300 or 338 lapua AICS style magazine? How is that setup working for others?

Kc

 

[mcfred]

300WSM.

If you're bored you can modify the 5-round .308 AICS to work too. It'll hold 3-4 rounds. With 4 though, you can't have the mag in and the bolt closed since the stack won't compress any more.

 

[VKC]

Depends on how much velocity you want to get and your barrel length.

I was getting 2950fps with 180gr Bergers from a 28" barrel in a short action with Alpha mags. To me that isn't any compromise. However I had to notch my feed ramps to get reliable feeding. I could eject an unfired round without problems.

Most people will give you their opinion only having owned one or the other not both. And also mostly because that is what they chose.

Also consider that if you are going to be pushing a 7wsm much faster you are going to sacrifice barrel life by a lot.

This is from someone that also has a long action 7wsm in a DTA platform, but then swapping out barrels is easy for a DTA.

Each (short vs long action) has it's advantages and disadvantages. Depends on what you think is the most important.


Sent from my iPhone using Tapatalk

 

[trauma1]

Tag


Trauma1

 

[KYS]

I run 162 AMAX, 168 Berger VLD's and 180gr Berger Hyrbids. They all perform very well given the amount of time that goes into the loading. You have to play with each load, write it down and ladder test. If you are willing to put in the time a SA receiver is all you will need.
Look into a gain twist 7mm barrel from Bartlein. It will help produce speed before it builds pressure.

 

[338RUM runner]

Are you guys running them outa a 300 or 338 lapua AICS style magazine? How is that setup working for others?

Kc

If it was me I would use the 300 Win AICS mags, the Lapua has a much bigger base than the 300. I use the 300 Win in my RUM's

 

[VKC]

FYI alpha mag max COAL IS 2.97" if that makes a difference.


Sent from my iPad using Tapatalk

 

[ZLBubba]

I had a Gradous 7WSM that I loved in a 591R short action. My ONLY regret is that I wish I had it built on an LA for the 180 Hybrids. I love the Berger Hybrids, so I was sold from the beginning on the 180s. It was tough to find a good node, but I did after a bit of load workup. You've got a lot more room to play with if you go with a long action, but an SA will work.

I will say this though, after seeing 180s bang steel at 1300 with ease at 2900fps, I just built a 7mm-300WM that slings 180s at 3200. God, I love the 7mm in all its permutations.