Tell me about this cartridge. My gunsmith thinks it is a reasonable option to the 7 mm STW, and is more accurate and would only require a reamer. I really know very little about it but he thinks its likely to improve accuracy with similar trajectory and be better suited to my magazine. Cases are mad from the 375 Ruger?, how difficult are they to find? He is pushing me pretty hard for the change.
7mm LRM
- Thread starter Elkman
- Start date
DrMike
Ballistician
- Nov 8, 2006
- 37,503
- 6,508
Think 375 Ruger necked down to 7mm. Case capacity approximates 7 STW.
http://site-media.net/gunwerks/7LRMarticle(1).pdf
http://www.gunwerks.com/Shooting-Systems/LR-1000
http://site-media.net/gunwerks/7LRMarticle(1).pdf
http://www.gunwerks.com/Shooting-Systems/LR-1000
Oldtrader3
Ammo Smith
- Nov 6, 2009
- 8,406
- 6
The design looks good. Plenty of capacity with the .375 Ruger case with no belt to mess up headspace. Neck is long enough to yield stabile, properly aligned neck to throat for increased accuracy. It appears that somebody has finally developed a stable platform for the 7mm Mag cartridges which is showing traits that will lead to stable and repeatable loads.
Darkhorse
Handloader
- Mar 14, 2014
- 823
- 185
I would do some internet searching on this cartridge before committing. I have read several sources that said it was hard to get accurate loads for this cartridge. Something about Gunwerks having a trick or two that's not being shared.
Maybe nothing to it at all but internet gossip.
Maybe nothing to it at all but internet gossip.
It's actually closer to a 7-300wm for case capacity. A 7-300wm is better IMO. There are tons of brass options and dies are pretty easy by using .300wm bushing dies. My OAL length with 162 Amax's seated with the bearing surface/boattail junction at the bottom of the neck is 3.604. In my 27" barrel they run 3190 with RWS brass (it gives up some velocity because it's thick but tough as heck) and 3260fps in my 28" barreled gun. I have 3 of them.
Oldtrader3
Ammo Smith
- Nov 6, 2009
- 8,406
- 6
Oh well, my 7mm Rem Mag is not what the hype said it would be but it still is a good cartridge. I never would have known the difference between the Rem Mag actual velocity with 160 Partitions and the advertised velocity if I had not chrono'ed my loads. However, the deer would not have known the difference either of 100 fps difference in muzzle velocity either.
I have used the 7mm Rem Mag for 50 years now and it has done well by me. I have had my current 7mm Mag, Mauser rifle for 40+ years and it still shoots the 160 Partition at 2900+ with very good accuracy. No sense getting in a state about Remington Marketeer's lying to me about muzzle velocity. What else is new?
I have used the 7mm Rem Mag for 50 years now and it has done well by me. I have had my current 7mm Mag, Mauser rifle for 40+ years and it still shoots the 160 Partition at 2900+ with very good accuracy. No sense getting in a state about Remington Marketeer's lying to me about muzzle velocity. What else is new?
Woodycreek
Handloader
- Aug 2, 2007
- 2,240
- 0
Bill,
I happen to know someone that has the reamer, dies, and brass for the 7 LRM :mrgreen: He is currently wanting on the donor rifle to get back from Winchester.
I happen to know someone that has the reamer, dies, and brass for the 7 LRM :mrgreen: He is currently wanting on the donor rifle to get back from Winchester.
Bill, Brian has dies and brass for the 7LRM. I believe he is going down that path pretty quick.
I think I'm doing a 7mm Mashburn Super Magnum for all of the reasons Nathan mentioned. Brass is made from the 300 Win Mag, and with a regular mag box you get plenty of COAL latitude.
I know you've got a couple 300 Win cases around too.
Besides, you don't wanna mess with them new fangled 375 Ruger cases, they are only based off a 100 year old cartridge. Ha!
I'll bet Brian will be along before too long. He smells blood in the water!
I think I'm doing a 7mm Mashburn Super Magnum for all of the reasons Nathan mentioned. Brass is made from the 300 Win Mag, and with a regular mag box you get plenty of COAL latitude.
I know you've got a couple 300 Win cases around too.
Besides, you don't wanna mess with them new fangled 375 Ruger cases, they are only based off a 100 year old cartridge. Ha!
I'll bet Brian will be along before too long. He smells blood in the water!
