Which 7mm to build???

[rscott5028]

I have a 7RM Sendero. It's a nice hunting rifle. I believe it would take deer at 1k. But, I find it pretty challenging to range whitetails at 800 yds with a pretty decent Leica 1200 CRF. If you can't range it, you'll have a hard time hitting it. ...never mind the wind or other real world LRH challenges.

In essence, I don't think the cartridge is going to matter much here. You need to pick one of the many that were mentioned and build a decent long range rig and start practicing.

My next 7mm will probably be the RSAUM. If Lapua would hurry up and start producing the brass, that'd pretty much seal the deal for me.

I have nothing against the big 7's. But, I personally don't have a need for one as I already have a 300WM.

You need one really good rifle to develop confidence/experience. Sell the Browning. Build on a 700 (or 700 clone/custom e.g. Stiller). I'd put the extra $$$ in the custom action and optics/range finder etc... before complicating things with a switch barrel.

-- richard

 

[Michael Eichele]

Hmmm... Somebody smell smoke? I think my brain is on fire! This switch barrel gun is a new concept to me but I know you have had success with it Michael. If I wanted the larger of the 2 to be 300wsm what would make a good 2nd cal. barrel (smaller cal. of course)? I could build the smaller one first and worry about the larger cal. barrel later. Do they have to be close in cartridge size or does that matter?

I guess this is why they call it a brainstorm!

The cartridges need to have the same head/base. You can get more than one bolt with different faces but it is a real pain to fit two bolts to one action. The lugs get cut and lapped on one, then the second one gets cut and lapped which changes the lugs in the action. It just goes round and round. It can be done but the goal is to keep it simple. Then you run into feeding problems. If your feed rails are cut for a 300RUM and then switch bolts and barrels for a 30-06 trying to use it as a repater is null and vice versa. The cartridges will pop up and out of the magazine or not feed through. Which leads you to needing a Badger or Seekins type bottom metal with different magzines. For me this is all just too much so I keep it to similar case heads. My one rifle (338Edge) shares another barrel in 300RUM. Same feed rails, same bolt face. I could use a barrel chambered in the WSMs or SARUMs with the long heavy bullets seated way out. The same will apply for my 308 and 6.5x284. Same bolt face and the rails are close enough I can feed either. My scope is within 2 clicks verticle and 11 clicks horizonatal between the two 338 and 300 barrels and their primary loads.

 

[shortpants]

Great advice Richard! Shut up and build it already! I love it! I think that is about where I'm getting to.

Michael, thanks for opening my eyes to another good option.

 

[trueblue]

How has the brass quality been for you guys that are shooting the 7LRM (7-375 Ruger) ?

 

[moombaskier]

The brass I purchased from Gunwerks which is headstamped Hornady 375 RUGER is getting ready to be loaded for the third round. I did notice a few with not so tight primer pockets from the few that loaded hot. I'll have to see how the rest do. I did shoot a sub 2" 3 shoot group today at 625yds. I've got 7 more to shoot tomorrow then it's time for round 3. I hope it holds up for at least 4.

 

[AaronSkipDavidson]

Did some research on the 7mm LRM yesterday 1-13-2012. The previous poster mentioned that Gunwerks will have brass and dies available at a reasonable cost. The prices are much higher that his report. I was told by a gentleman at Gunwerks that Hornady is making headstamped brass for Gunwerks. Cost is $2.80 each. The usual FL/seater die set is $180.

Hornady told me that it takes three forming dies costing $70- 90 each to alter the 375 Ruger brass to make the LRM case. Simply necking down the 375 brass is not enough as the neck becomes too short. Gunwerks bumps the shoulder back making a longer neck.

This proprietary case is costly regardless if you buy them or do it yourself.

Match Grade dies with bushing are going to be $175 or less, Brass is still slated for $1.25.

 

[Shumba]

I don't think you are going to po anybody but if your looking at elk at 1000 yards you are barking up the wrong tree trying to make something fit instead of building an elk rifle that will do the job.

For deer and antelope considering your short barrel and dislike for recoil you listed cartridges that are just the opposite. The 280 AI would be a good choice for you. Then if you go elk hunting long range then build a large caliber elk rifle.

+1 on the above. For the reasons listed a 280 AI would be a perfect fit. I have a 1-9 Kreiger 25" barrel, throated for Berger 180's. .188 Freebore. The 180's will do right at 2900 and the 168's 3000 fps with good brass life. Take note that the long throat allows these slightly higher than ave vel as compared to shorter throated chambers, and you will probably not be able to achieve these velocities with a shorter throat. The .188 freebore will not allow the 140's to be used so this would be dedicated to 160 NAB's or heavier bullets. Another thing about the 280 AI is that much like the 6.5x284 is that they ALL seem to shoot! The 280 AI is One to consider.