long range project 7 mag
- Thread starter baboltin
- Start date
Ok here goes..
Yes imo you are getting the wrong barrel. I'm not a 7mm guy so take what I say with a gr of salt.
If you are building a long range gun you want to optimize all the factors to have the best gun you can for the given purpose. Long range is 800+yards that's a long ways. if you are going to shoot that far it's important to get the setup right.
If this gun is for paper and out of state hunting then your twist is a handicap. The heavy bullets will out perform the light ones. That's just the math talking there. The sweet spot for 7mag is not 120 gr.
If we are talking mid range 600 yards max and just a hunting gun then you can run with what you have. It won't be a tack driver with the vld 140 gr bullets but it will shoot.
The monolithic ammo is pretty amazing, definitely the wave of the future here in calif. That bc on their 116gr hv bullet is nothing to laugh at and it will work in your gun
Yes imo you are getting the wrong barrel. I'm not a 7mm guy so take what I say with a gr of salt.
If you are building a long range gun you want to optimize all the factors to have the best gun you can for the given purpose. Long range is 800+yards that's a long ways. if you are going to shoot that far it's important to get the setup right.
If this gun is for paper and out of state hunting then your twist is a handicap. The heavy bullets will out perform the light ones. That's just the math talking there. The sweet spot for 7mag is not 120 gr.
If we are talking mid range 600 yards max and just a hunting gun then you can run with what you have. It won't be a tack driver with the vld 140 gr bullets but it will shoot.
The monolithic ammo is pretty amazing, definitely the wave of the future here in calif. That bc on their 116gr hv bullet is nothing to laugh at and it will work in your gun
Okay I'll give this a go.
Actually twist rate is related more to bullet length than to weight, which is why larger calibers (heavier bullets in general) don't have higher and higher twist rates as you go up in caliber. Each caliber has a sweet spot for bullet weight, and the twist rate on the barrel should be consistent with that. Low twist rate on a longer bullet fails to stabilize it, whereas shorter bullets are stabilized with a lower spin rate. So with a 1:11 twist your best accuracy will be with shorter (lighter) bullets. Trouble with that is the lighter bullets have lower BC and get blown around more by the wind because they take more time reaching the target. That's not obvious because muzzle velocity is always higher for lighter bullets; but velocity at >300 yards is what matters, and BC is what maintains velocity. So you are giving up a key advantage of 7mm mag (long range accuracy) by going with low twist rate.
Actually twist rate is related more to bullet length than to weight, which is why larger calibers (heavier bullets in general) don't have higher and higher twist rates as you go up in caliber. Each caliber has a sweet spot for bullet weight, and the twist rate on the barrel should be consistent with that. Low twist rate on a longer bullet fails to stabilize it, whereas shorter bullets are stabilized with a lower spin rate. So with a 1:11 twist your best accuracy will be with shorter (lighter) bullets. Trouble with that is the lighter bullets have lower BC and get blown around more by the wind because they take more time reaching the target. That's not obvious because muzzle velocity is always higher for lighter bullets; but velocity at >300 yards is what matters, and BC is what maintains velocity. So you are giving up a key advantage of 7mm mag (long range accuracy) by going with low twist rate.
Baboltin
No worries even some of us old veterans, we ether forget or don't know ether.. it is a constant learning curve.
I studied this stuff then get side tracked with every day worries or day to day grunge. and forget things.
Don
Nice description.
It is a constant learning curve for me too. there are so many variables. just when you think you got it changes just like computers. always getting better. I try to read up on it went I have time.
I too like the 7 mm mag, but it's a toss up with the 338 lapua.
hoping for the near future.
Ghost
No worries even some of us old veterans, we ether forget or don't know ether.. it is a constant learning curve.
I studied this stuff then get side tracked with every day worries or day to day grunge. and forget things.
Don
Nice description.
It is a constant learning curve for me too. there are so many variables. just when you think you got it changes just like computers. always getting better. I try to read up on it went I have time.
I too like the 7 mm mag, but it's a toss up with the 338 lapua.
hoping for the near future.Ghost