7mm Rem Mag vs 7mm-300 Win Mag

[bigmo101]

I've got a Proof Research barrel on order. 28" with a 1:8 twist. I have a bunch of H1000. My plan is to use the 175 ELD-X bullet. I just wanted to see how many people have successfully pushed that bullet to 3000 fps.

If not to many people have, I would just go with a 7mm-300 Win Mag. My preference is Nosler brass. I want to keep it in the 3000 fps or right about in that area. I know the 7mm-300 will get it the easily. Any info would be greatly appreciated!

 

[Lrt307]

I've got a Proof Research barrel on order. 28" with a 1:8 twist. I have a bunch of H1000. My plan is to use the 175 ELD-X bullet. I just wanted to see how many people have successfully pushed that bullet to 3000 fps.

If not to many people have, I would just go with a 7mm-300 Win Mag. My preference is Nosler brass. I want to keep it in the 3000 fps or right about in that area. I know the 7mm-300 will get it the easily. Any info would be greatly appreciated!

3000 is a walk in the park for the 7rem 26" barrel. I was shooting 71 grains retumbo 3085 fps.

 

[MudRunner2005]

Yep, a 28" 7mm RemMag with a 175-180gr bullet should not have a problem reaching 3K+.

Since you have a 1:8 twist, you should look into the new Berger 195 EOL's...

 

[bigmo101]

3000 is a walk in the park for the 7rem 26" barrel. I was shooting 71 grains retumbo 3085 fps.

Was that with a 180? Also, what was your coal? Just want to get a feel for magazine length.

 

[bigmo101]

Since you have a 1:8 twist, you should look into the new Berger 195 EOL's...

I was doing some ballistic calculation. I figured I'd get about 2850 fps pushing the 195. Less than a quarter moa of wind and 2 moa of drop. I was using the 175 ELD-X at 3000 fps in comparison. Not sure if I'm missing something.

 

[Lrt307]

Was that with a 180? Also, what was your coal? Just want to get a feel for magazine length.

3085 was with 71 grains retumbo and eldx 175. I also run 71 grains retumbo 3080 with berger 180. My base to ogive is 2.693 with a berger 180 and 2.715 with eldx. Puts me right near .025 off lands.

 

[bigmo101]

What would be the measurement to the tip? Just wondering for magazine length and amount of freebore to accommodate the length in the chamber.

 

[MudRunner2005]

I was doing some ballistic calculation. I figured I'd get about 2850 fps pushing the 195. Less than a quarter moa of wind and 2 moa of drop. I was using the 175 ELD-X at 3000 fps in comparison. Not sure if I'm missing something.

With a 28" barrel, and the right powder and brass, you should be able to get close to 3,000 with the 195's... Try inputting them at around 2,950 (more realistic number), but you could have a fast barrel, which could get you to 3K... Never know till you try.

Also, with the 7mmRM in a Rem 700 action, you would be able to seat the 195's way out there near the rifling (I set all my Bergers at 0.015" off the lands).

 

[MudRunner2005]

What would be the measurement to the tip? Just wondering for magazine length and amount of freebore to accommodate the length in the chamber.

For measuring if they will fit in the magazine, yes, you measure COAL to the bullet tip. To measure to the lands, you use a cartridge length gauge. And to measure true cartridge length and bullet runout, you need a comparator to measure from base-to-ogive.

 

[bigmo101]

Mudrunner I see your point. I guess my priority is that it fits in the magazine easily and build the chamber around the dummy round. The 175 gr ELD-X and the 180 berger hybrid would be the lightest I would load in the rifle. Should I build a dummy round using the that for the chamber dimensions?

 

[MudRunner2005]

Mudrunner I see your point. I guess my priority is that it fits in the magazine easily and build the chamber around the dummy round. The 175 gr ELD-X and the 180 berger hybrid would be the lightest I would load in the rifle. Should I build a dummy round using the that for the chamber dimensions?

If you want a custom chamber cut, then yes, you will need a custom reamer built to your needs. It would be best to contact the reamer manufacturer to see what they prefer you do. They most-likely already have bullet specs, and you'll only need to tell them what COAL you need to be at to keep you inside of mag length with a particular bullet.