I finally got a chronograph to test my loads. I have been loading for a while now and have only been looking for the most accurate load, but now I have some numbers. I am wondering what speeds you guys with 18" Gas guns are getting? I chronoed a load I have been using today and averaged out at 2457. Is that too low? Should I be looking for more? Load is 40G 8208XBR under 168 Hornady In Lapua brass, CCI primer.
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Re: Questions about your 308 FPS
I run 168gr Hornady A-max bullets with 44.0 gr Varget from my 18" DPMS LR308 and get 2570 +/- FPS. The gun shoots a legit repeatable 0.50 MOA and sometimes less.
I'd say your speed is good if it is getting you good groups at your preferred distance.
In my gun, the bullet will drop 55 inches from the 200 yard zero at 500 yards. My concern would be at 110 fps less, you'll start getting more drop than that.
I run 168gr Hornady A-max bullets with 44.0 gr Varget from my 18" DPMS LR308 and get 2570 +/- FPS. The gun shoots a legit repeatable 0.50 MOA and sometimes less.
I'd say your speed is good if it is getting you good groups at your preferred distance.
In my gun, the bullet will drop 55 inches from the 200 yard zero at 500 yards. My concern would be at 110 fps less, you'll start getting more drop than that.
Re: Questions about your 308 FPS
That's a light load I bet you could go 42 grains for 2550ish fps.
That's a light load I bet you could go 42 grains for 2550ish fps.
Re: Questions about your 308 FPS
That powder was designed for 155 Palma bullets??? Got a few cans for the 2156 155 smk. Haven't played yet. I'd go varget..... Just my opinion.
That powder was designed for 155 Palma bullets??? Got a few cans for the 2156 155 smk. Haven't played yet. I'd go varget..... Just my opinion.
Re: Questions about your 308 FPS
That's slow, but you are running 3.3 grains(ish) under the max load. Up the charge and see what happens
That's slow, but you are running 3.3 grains(ish) under the max load. Up the charge and see what happens
Re: Questions about your 308 FPS
That round run at 2457 all the way to 2600 still goes subsonic between 900 and 1000yrds. I slowed my bolt gun down to 2550 b/c it was more accurate and no real advantage in burning the extro powder.
That round run at 2457 all the way to 2600 still goes subsonic between 900 and 1000yrds. I slowed my bolt gun down to 2550 b/c it was more accurate and no real advantage in burning the extro powder.
Re: Questions about your 308 FPS
I'd say that's a light charge for a 168. I'm getting 2566 using a 178 bullet and 4064. I get 2688 using 4895 with no signs of pressure. I get great accuracy out of both loads. If you want to shoot out to 1k I think you need to be right at 2550 or above...
I'd say that's a light charge for a 168. I'm getting 2566 using a 178 bullet and 4064. I get 2688 using 4895 with no signs of pressure. I get great accuracy out of both loads. If you want to shoot out to 1k I think you need to be right at 2550 or above...
Re: Questions about your 308 FPS
I'd argue that you need a certain velocity to hit a sweet spot. You need to reach a certain velocity to stabilize the bullet to reach out to 1 k yards and that happens to be 2550 minimum. Now if you are not concerned with shooting that far out then you are right, velocity doesn't matter.
I'd argue that you need a certain velocity to hit a sweet spot. You need to reach a certain velocity to stabilize the bullet to reach out to 1 k yards and that happens to be 2550 minimum. Now if you are not concerned with shooting that far out then you are right, velocity doesn't matter.
Re: Questions about your 308 FPS
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GhostFace</div><div class="ubbcode-body">I'd argue that you need a certain velocity to hit a sweet spot. You need to reach a certain velocity to stabilize the bullet to reach out to 1 k yards and that happens to be 2550 minimum. Now if you are not concerned with shooting that far out then you are right, velocity doesn't matter. </div></div>Velocity sweet-spots are often found much lower than one would predict: One bullet manufacturer discovered that the best accuracy of one of its most popular match bullets, one designed to be driven at around 2700fps, was to be found around 2400fps.
...And velocity doesn't stabilize bullets.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GhostFace</div><div class="ubbcode-body">I'd argue that you need a certain velocity to hit a sweet spot. You need to reach a certain velocity to stabilize the bullet to reach out to 1 k yards and that happens to be 2550 minimum. Now if you are not concerned with shooting that far out then you are right, velocity doesn't matter. </div></div>Velocity sweet-spots are often found much lower than one would predict: One bullet manufacturer discovered that the best accuracy of one of its most popular match bullets, one designed to be driven at around 2700fps, was to be found around 2400fps.
...And velocity doesn't stabilize bullets.
Re: Questions about your 308 FPS
What stabalizes a bullet? I never experieced keyholing but it was explained to me that when the bullet is starting to peter out it becomes unstable in flight and therefore key holes into a target or may not even make hit the target. And while I do agree some light charges can be extremely accurate but 2400 fps load I would'nt use for a 1k because I doubt it's going to get there accurately...
What stabalizes a bullet? I never experieced keyholing but it was explained to me that when the bullet is starting to peter out it becomes unstable in flight and therefore key holes into a target or may not even make hit the target. And while I do agree some light charges can be extremely accurate but 2400 fps load I would'nt use for a 1k because I doubt it's going to get there accurately...
Re: Questions about your 308 FPS
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GhostFace</div><div class="ubbcode-body">What stabalizes a bullet? I never experieced keyholing but it was explained to me that when the bullet is starting to peter out it becomes unstable in flight and therefore key holes into a target or may not even make hit the target. And while I do agree some light charges can be extremely accurate but 2400 fps load I would'nt use for a 1k because I doubt it's going to get there accurately... </div></div>
The barrel’s rifling makes the bullet spin. Different bullets need different spin rates to perform efficiently. As a general rule, a longer bullet needs a higher spin rate than a shorter bullet to effectively stabilize. I shoot longer bullets (208 Amax and 155 Lapua Scenars) out of my Savage 110fp, which has a 1:10 twist rate and will adequately spin those bullets.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GhostFace</div><div class="ubbcode-body">What stabalizes a bullet? I never experieced keyholing but it was explained to me that when the bullet is starting to peter out it becomes unstable in flight and therefore key holes into a target or may not even make hit the target. And while I do agree some light charges can be extremely accurate but 2400 fps load I would'nt use for a 1k because I doubt it's going to get there accurately... </div></div>
The barrel’s rifling makes the bullet spin. Different bullets need different spin rates to perform efficiently. As a general rule, a longer bullet needs a higher spin rate than a shorter bullet to effectively stabilize. I shoot longer bullets (208 Amax and 155 Lapua Scenars) out of my Savage 110fp, which has a 1:10 twist rate and will adequately spin those bullets.
Re: Questions about your 308 FPS
He didn't say anything about 1K. While it stays supersonic at 1K by about 75 FPS the drop in 425 inches. The air is some of the thickest on earth around here and the humidity is twice that. I bet he's only about 5 foot above sea level.
He didn't say anything about 1K. While it stays supersonic at 1K by about 75 FPS the drop in 425 inches. The air is some of the thickest on earth around here and the humidity is twice that. I bet he's only about 5 foot above sea level.
Re: Questions about your 308 FPS
I use 43-43.3 grains on my 18" bolt gun with xbr and lapua brass 168 Amax or smk . Different velocity cause its not a gas gun but its not a hot load.
I use 43-43.3 grains on my 18" bolt gun with xbr and lapua brass 168 Amax or smk . Different velocity cause its not a gas gun but its not a hot load.
Re: Questions about your 308 FPS
I have a DPMS LR308L which also has a 18 inch barrel. My chrono shows 175 FGMM at 2530 FPS. I have been running the Hornady 178 HPBT and I find that 43.1 varget matches the FGMM at 2530 or so.
I also tried 8208XBR, but I felt that I couldn't get the velocities that I got with Varget.
Hope this helps.
Kind regards,
Jared
I have a DPMS LR308L which also has a 18 inch barrel. My chrono shows 175 FGMM at 2530 FPS. I have been running the Hornady 178 HPBT and I find that 43.1 varget matches the FGMM at 2530 or so.
I also tried 8208XBR, but I felt that I couldn't get the velocities that I got with Varget.
Hope this helps.
Kind regards,
Jared
