What is a 7MM LRM ? The difference between it and a 7mm WSM ?
7mm LRM
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429421Cowboy
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Lower pressure ? How can you drive a bullet faster with lower pressure ?
does the 375 have a belt? I thought that was another benefit for some people.
There's a fair amount of info on the cartridge on here. It's a staple for the Gunwerks guys, and you can buy brass and dies from them.
I don't own one, but the standard expectation I believe is 3050fps on 73.0 gr of H1000 for Berger 180's out of a 25.5-26.0" barrel. I believe that is a little better than your average 7-300WSM.
You will see quotes from the Gunwerks guys, that it is very similar to the 6.5-284 dimensionally, and it benefits from the same case capacity to bullet diameter benefits, therefore providing improved efficiency.
I bought worked over 700 in 7STW planning to re-barrel to the LRM, but found it shoots 168Bergers at 3120 extremely well and with a LOT less felt recoil than I expected, so the plan is still on hold. I will say that while Gunwerks markets the brass, the limited accessibility of brass would be a concern, it is even a problem on my SAAMI STW.
I don't own one, but the standard expectation I believe is 3050fps on 73.0 gr of H1000 for Berger 180's out of a 25.5-26.0" barrel. I believe that is a little better than your average 7-300WSM.
You will see quotes from the Gunwerks guys, that it is very similar to the 6.5-284 dimensionally, and it benefits from the same case capacity to bullet diameter benefits, therefore providing improved efficiency.
I bought worked over 700 in 7STW planning to re-barrel to the LRM, but found it shoots 168Bergers at 3120 extremely well and with a LOT less felt recoil than I expected, so the plan is still on hold. I will say that while Gunwerks markets the brass, the limited accessibility of brass would be a concern, it is even a problem on my SAAMI STW.
I was referring to the 7-300 Win Mag not a 7-300wsm. 3050fps is pretty easy for a 7-300wm in a 26" barrel. The loads are even pretty much the same between the two. Why limit yourself to their brass when you can do a 7-300wm and use readily available brass from many different sources including Lapua (if you can find it) and RWS (which is as tough as it gets). You can also use a 300wm bushing die to size your cases to make life easier. My 7-300wm has a 27" Schneider barrel and get's 3160fps with 162 Amax's using 73grs of H-1000 in RWS cases which are slower and have less capacity than other brands but last forever.
I built two 7mm/375s recently, not the 7mm LRM. Reason is brass availability. I have always seen 375 Ruger brass on the shelves when there is nothing else. I had the dies necessary to make this wildcat. Only thing I needed was the reamer which I buy regardless of build. Life is too short to use reamer that isn't spec'd out.
I would agree that the 7mm-300 win mag would be easy to make IF the brass was available.
I would agree that the 7mm-300 win mag would be easy to make IF the brass was available.
Just read about the 7mm Rogue.
7mm Rogue » R Bros Rifles
It would appear to be pretty much the same as the 7mm/300 win with "some measurement relationships with todays "accuracy" cartridges" quote copied from article.
IMO the 7mm Mashburn/ 7mm-300 win mag 7 LRM and 7mm/375 Ruger are pretty much the same. Variations will be in the throating based on who requests the reamer specifications. Pick one and run with it with indistinguishable performance.
7mm Rogue » R Bros Rifles
It would appear to be pretty much the same as the 7mm/300 win with "some measurement relationships with todays "accuracy" cartridges" quote copied from article.
IMO the 7mm Mashburn/ 7mm-300 win mag 7 LRM and 7mm/375 Ruger are pretty much the same. Variations will be in the throating based on who requests the reamer specifications. Pick one and run with it with indistinguishable performance.
300wm brass is available. I just bought 150 rounds of Nosler brass last week. Shooters Pro Shop had about 30 boxes of seconds. The good thing about it is the caliber is popular enough you'll see it for sale typically within a week if you watch for it.
You are right in that 375 Ruger is on the shelves a lot. The down side is having to buy several sets of dies to neck it from 375 to 7mm. One pass through my 7-300wm die turns 300wm into 7-300wm.
If your limited to standard magazine lengths the 7-300wm doesn't give up much to a 7STW. Seated long a STW is 100+fps faster.
You are right in that 375 Ruger is on the shelves a lot. The down side is having to buy several sets of dies to neck it from 375 to 7mm. One pass through my 7-300wm die turns 300wm into 7-300wm.
If your limited to standard magazine lengths the 7-300wm doesn't give up much to a 7STW. Seated long a STW is 100+fps faster.
