Badlands Precision Bullets thread - From BC to terminal ballistics

[Northkill]

I am going to try StaBall-Match which is slightly slower than Varget but considerably faster than LVR. Have already reached 3242 fps with the BD2 bullet using 53 gr of LVR in the 24" barrel and the LRP brass with no apparent overpressure signs yet. Have not been able to do that with Bullet#1. Max speed so far is 3178 fps with 52 LVR. 53 gr gave only 3129. Not sure what is going on there but I was very careful to measure our 53 gr and it was clearly compressing with bullet seating like in the BD2. Have you been able to safely get 3200 fps from a 308Win? Like to see that recipe and see how it compares with what I am using.

As stated earlier, we have no 30 cal rifles at the moment and have no experience with said projos in the 308 Win. Most of our experience has been with the 125 gr in 6.5 which we tried in 4 different 6.5's. Unfortunately, none of them would take to the bullet in terms of accuracy but we've found them to generally pressure up a little faster than similar weight C&C's and the velocity to pressure was a little disappointing. We had the same results in the .224 & .277 trials.

On the "ridged" bullets, we've found when loading by conventional standards, pressure indications came earlier than expected. In at least one instance, we concluded that the neck grip on the projo was reduced by the "ridges" as well and it was jamming into the lands by the primer before the powder ignition which, of course, gives pressure spikes. In this case, we did the recommended crimp which gave a significant velocity boost as well as in accuracy. It also opened the door to faster powders. All interesting stuff. Lots of folks are leaving a lot on the table with this bullet design because it is only realized when one is willing to color outside the traditionally accepted boundaries.

Now, to be fair, the velocities you're achieving with the 150 in the 308 Win are impressive from my perspective. Maybe we were leaving potential on the table with the 125's in our applications.

Keep chasing perfection as you've been. We all benefit.

 

[nralifer]

As stated earlier, we have no 30 cal rifles at the moment and have no experience with said projos in the 308 Win. Most of our experience has been with the 125 gr in 6.5 which we tried in 4 different 6.5's. Unfortunately, none of them would take to the bullet in terms of accuracy but we've found them to generally pressure up a little faster than similar weight C&C's and the velocity to pressure was a little disappointing. We had the same results in the .224 & .277 trials.

On the "ridged" bullets, we've found when loading by conventional standards, pressure indications came earlier than expected. In at least one instance, we concluded that the neck grip on the projo was reduced by the "ridges" as well and it was jamming into the lands by the primer before the powder ignition which, of course, gives pressure spikes. In this case, we did the recommended crimp which gave a significant velocity boost as well as in accuracy. It also opened the door to faster powders. All interesting stuff. Lots of folks are leaving a lot on the table with this bullet design because it is only realized when one is willing to color outside the traditionally accepted boundaries.

Now, to be fair, the velocities you're achieving with the 150 in the 308 Win are impressive from my perspective. Maybe we were leaving potential on the table with the 125's in our applications.

Keep chasing perfection as you've been. We all benefit.

There are two points that can affect accuracy. One is the clearance between the bullet and the wall of the lead portion of the throat. It ideally should be 0.0004" on each side. That assures that the bullet enters the rifling straight. The second is jump. Usually 0.025" works well but doing a 2 shot jump ladder at 0.010" increments and focusing on the jump that gives the tightest 2 shot group in the ladder.

 

[nralifer]

As stated earlier, we have no 30 cal rifles at the moment and have no experience with said projos in the 308 Win. Most of our experience has been with the 125 gr in 6.5 which we tried in 4 different 6.5's. Unfortunately, none of them would take to the bullet in terms of accuracy but we've found them to generally pressure up a little faster than similar weight C&C's and the velocity to pressure was a little disappointing. We had the same results in the .224 & .277 trials.

On the "ridged" bullets, we've found when loading by conventional standards, pressure indications came earlier than expected. In at least one instance, we concluded that the neck grip on the projo was reduced by the "ridges" as well and it was jamming into the lands by the primer before the powder ignition which, of course, gives pressure spikes. In this case, we did the recommended crimp which gave a significant velocity boost as well as in accuracy. It also opened the door to faster powders. All interesting stuff. Lots of folks are leaving a lot on the table with this bullet design because it is only realized when one is willing to color outside the traditionally accepted boundaries.

Now, to be fair, the velocities you're achieving with the 150 in the 308 Win are impressive from my perspective. Maybe we were leaving potential on the table with the 125's in our applications.

Keep chasing perfection as you've been. We all benefit.

Surprising you don't have a 30 cal. I have always loved the 308Win. It is so versatile and components are always available somewhere. It is also easy to get to shoot accurately and it is very easy on barrels. With the 150 BD2 you have seen it is easy to get safe loads going 3150 fps. I have done most of my hunting with that bullet and the first generation of that bullet, and I kid you not, it is the equivalent of a 300 Win mag of WSM shooting lead cores within 900 yards. I really haven't explored what can be done with the 175 308BD2 and SRP brass. A 0.6 G1BC beats 185 Juggernaut and on game will definitely out penetrate it.

 

[akmtnhnt]

The COAL are 2.860" for Bullet#1 and 2.900 For the BD2 which has a longer ogive.

So then ya, that's exactly what's happening. Bullet #1 is running at about 6000psi lower than bullet 2 with the exact same powder charge. Estimated ~59k vs 65k. I would expect bullet #2 to always be faster in that scenario.
What would also be interesting is if you bumped the powder charge 1.1 grains for bullet 1, to get an estimated 65kpsi, same as bullet 2, and see if the velocity spread becomes minimal. I suspect it will.

I noticed you use lever revolution a bunch. I also really like that powder for anything in the 308 sized case range.

 

[akmtnhnt]

Surprising you don't have a 30 cal. I have always loved the 308Win. It is so versatile and components are always available somewhere. It is also easy to get to shoot accurately and it is very easy on barrels. With the 150 BD2 you have seen it is easy to get safe loads going 3150 fps. I have done most of my hunting with that bullet and the first generation of that bullet, and I kid you not, it is the equivalent of a 300 Win mag of WSM shooting lead cores within 900 yards. I really haven't explored what can be done with the 175 308BD2 and SRP brass. A 0.6 G1BC beats 185 Juggernaut and on game will definitely out penetrate it.

I wish I could stabilize those 175's for my 3006, but it's a 1-11.

 

[nralifer]

So then ya, that's exactly what's happening. Bullet #1 is running at about 6000psi lower than bullet 2 with the exact same powder charge. Estimated ~59k vs 65k. I would expect bullet #2 to always be faster in that scenario.
What would also be interesting is if you bumped the powder charge 1.1 grains for bullet 1, to get an estimated 65kpsi, same as bullet 2, and see if the velocity spread becomes minimal. I suspect it will.

I noticed you use lever revolution a bunch. I also really like that powder for anything in the 308 sized case range.

 

[nralifer]

Show us the calculations it must take into account the powder compression.

 

[Quintus]

Really interesting read here. After following this thread for a while I decided to give the 125 BD2 a run. my goal was to run it in a 6.5RPM with RL26. I already have a fantastic load with bullet '1' of very similar weight, but I like to see what is over the next hill so I ordered 100. I was really surprised how fast these pressured up in the RPM and was a little dejected. Decided to run a ladder in the PRC with the same powder and WOW! The velocity goal was 3400. I ran up to 60.8 grains on 2x fired Hornady brass with a Fed 210M primer with no primer flattening or ejector marks and easy extraction. the next range trip will be checking SD and accuracy at 60.3gr at 3,425 ish from a 24" barrel. That is 1/2 grain under my bullet '1' load and 40FPS slower, but I have good case fill and if this load will shoot, it should still really smack at 600. It looks like enough snow will be gone from my 400 yard range this weekend so I am pretty excited to see how these will group. It is interesting how closely these tracked to the bullet '1' velocity curve in the PRC and how drastically different they tracked in the RPM.

 

[nralifer]

I wish I could stabilize those 175's for my 3006, but it's a 1-11.

I did some more testing this time with StaBall Match. SBM is faster burning than LVR so I was more prone to reach maximum pressure. I'm showing the data in the picture. At 50 gr the powder is compressed by both bullets. For the BD2 primer flattening was observed at 51 gr. For Bullet #1 it was observed at 52.5 gr. In both instances the powder level reached the mid neck and higher. In other words the powder was compressed maximally. At 52.5 gr Bullet#1 is going only 23 fps faster than the BD2. The difference in speed is minimal, and because of the large BC difference, the difference is made up within the first 50 yds by the BD2. Pics 2and 3 show JBM trajectory charts for both bullets. At 1000 yds Bullet #1 is at the speed of sound having only 426 ft-lbs of energy. The BD2 at 1000 yds is going 1720 fps with 985 ft-lbs of energy. 231% more energy. I'll concede that multiple ridges might marginally improve MV but at a huge expense in In BC. Given these test results, the small differences in MV don't come close to the losses in BC that result. In fact to equal the energy of the BD2 at 1000 yds, Bullet #1would have to start out at 4065 fps (chart 3), impossible to obtain in the 308 Win for sure.

 

[Northkill]

Really interesting read here. After following this thread for a while I decided to give the 125 BD2 a run. my goal was to run it in a 6.5RPM with RL26. I already have a fantastic load with bullet '1' of very similar weight, but I like to see what is over the next hill so I ordered 100. I was really surprised how fast these pressured up in the RPM and was a little dejected. Decided to run a ladder in the PRC with the same powder and WOW! The velocity goal was 3400. I ran up to 60.8 grains on 2x fired Hornady brass with a Fed 210M primer with no primer flattening or ejector marks and easy extraction. the next range trip will be checking SD and accuracy at 60.3gr at 3,425 ish from a 24" barrel. That is 1/2 grain under my bullet '1' load and 40FPS slower, but I have good case fill and if this load will shoot, it should still really smack at 600. It looks like enough snow will be gone from my 400 yard range this weekend so I am pretty excited to see how these will group. It is interesting how closely these tracked to the bullet '1' velocity curve in the PRC and how drastically different they tracked in the RPM.

That is impressive results in the PRC. Once you get over 3k impact speeds you may have mixed on-game terminal results. These shine in lower velocity impacts (under 3k). Keep us informed on your grouping results.

 

[Northkill]

Surprising you don't have a 30 cal. I have always loved the 308Win. It is so versatile and components are always available somewhere. It is also easy to get to shoot accurately and it is very easy on barrels. With the 150 BD2 you have seen it is easy to get safe loads going 3150 fps. I have done most of my hunting with that bullet and the first generation of that bullet, and I kid you not, it is the equivalent of a 300 Win mag of WSM shooting lead cores within 900 yards. I really haven't explored what can be done with the 175 308BD2 and SRP brass. A 0.6 G1BC beats 185 Juggernaut and on game will definitely out penetrate it.

Have had a 30/06 and a 308 in the past. Been looking at the 300 Norma for another toy. Or just might jump up to the 338 right away.

 

[nralifer]

That is impressive results in the PRC. Once you get over 3k impact speeds you may have mixed on-game terminal results. These shine in lower velocity impacts (under 3k). Keep us informed on your grouping results.

I get 3030 fps from my 6.5x47 Lapua using our 135 gr SBD2 in a 7 twist barrel using SB6.5

 

[Quintus]

That is impressive results in the PRC. Once you get over 3k impact speeds you may have mixed on-game terminal results. These shine in lower velocity impacts (under 3k). Keep us informed on your grouping results.

That is interesting, I did not know these were suspect on terminal performance at hi impact velocity?

 

[nralifer]

Have had a 30/06 and a 308 in the past. Been looking at the 300 Norma for another toy. Or just might jump up to the 338 right away.

I have to say, the 300 Norma is a hell of a cartridge . It can be very versatile.