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Turkeytider
06-09-2023, 01:27 PM
Well, first range trip with my new Model 12 LRPV in .223. Tried zeroing a Frontier ( Hornady ) 55 grain OTM. Gun threw them all over the lot! Nowhere close to any kind of group from which to adjust. Figured that either the barrel ( 1:7 ) won`t stabilize them or the bore sighting was not correct somehow. Had a few 68 grain OTM Frontier loads so gave them a try. Dialed back to the bore sight settings and started over. Two three round groups later the load was zeroed. Shot two more sub-MOA groups right at or very close to POA. VERY satisfied. Think that this is going to be a fun gun to shoot!
Vortex Diamondback Tactical 4-16X 44 scope.

charlie b
06-09-2023, 05:29 PM
Congratulations!

If anything, the 1-7 twist over stabilizes the shorter 55gn bullets. It is enough to stabilize 80gn and maybe 90gn .22cal bullets.

Turkeytider
06-09-2023, 06:45 PM
Congratulations!

If anything, the 1-7 twist over stabilizes the shorter 55gn bullets. It is enough to stabilize 80gn and maybe 90gn .22cal bullets.

Well Charlie, whatever it was doing, it was putting bullets all over the place. I could barely keep them on the target sheet!

Turkeytider
06-10-2023, 07:29 AM
Congratulations!

If anything, the 1-7 twist over stabilizes the shorter 55gn bullets. It is enough to stabilize 80gn and maybe 90gn .22cal bullets.

To be honest, never heard of " over stabilization " of a bullet. What does that do, if anything, to impact performance?

CFJunkie
06-10-2023, 09:05 AM
Pardon me in advanced for this long post, but I believe that the data will let you see that there is no easy answer for which bullet will perform best in your new barrel.

I believe that your rifle is telling you that it might shoot bullets in the 69 and maybe up to the 77-grain range better than the lighter bullets.
You might also try the Hornady 73 gr ELD-Ms or the 75 gr ELD-Ms. They aren't as expensive as the Berger, Nosler or Sierra heavy bullets.

Here is some data that might let you see how one particular rifle barrel performs with different powders and bullets, no matter how confusing and illogical it might seem.

The 73 gr ELD-Ms shoot more accurately in my Savage 12 FV rifle with a 26-in 1:9 twist barrel than the 75 ELD-Ms.
But my 1:9 twist consistently shoots 77 gr bullets accurately so the 75 gr bullet weight shouldn't have caused the difference.
The same 1:9 twist rifle shot 77 SMKs to a 0.235-in average for 10 5-round groups at 100 yards using N540 powder during my last session. (We'll see if N540 accuracy holds up for a larger sample.)
77 SMKs averaged 0.292-in average for 90 groups with IMR4166 powder, and 0.289-in average for 83 groups with N140 powder.
77 TMKs averaged 0.279-in average for 205 groups with IMR4166 powder, and 0.282-in average for 61 groups N140 powder.
77 Nosler CCs averaged 0.280-in groups for 12 groups with H4895 powder, and 0.227-in average for 9 groups with IMR4166 powder.
77 Berger OTMs averaged 0.282-in average for 17 groups with N140 powder.
73 ELD-Ms shot a 0.264-in average for 8 groups with H4895 powder and 0.273 for 7 groups with N140 powder a few months ago. (I need to find more of these.)
75 ELD-Ms shot 0.375-in average for 4 groups with N140 powder at about the same time. (I was surprised that the 75 ELD-Ms did so poorly.)
69 SMKs shot a 0.235-in average for 21 groups with N540 powder.
69 SMKs shot a 0.289-in average for 32 groups with N140 powder and a 0.292-in average for 93 groups with IMR4166 powder.
69 Nosler CCs shot a 0.310 average for 13 groups with IMR4166 powder.
69 RMR shot .0296-in average for 11 groups with N140 powder.
(2000 69 RMR bullets cost about the same as 500 SMKs so if you want a bargain heavy bullet that shoots pretty well, this might be your best bet.)

In comparison, lighter bullets didn't shoot as well in my Savage 12 FV.
50 gr Berger Varmint FBs averaged 0.390 with N133 powder.
52 gr Hornady ELD-Ms averaged 0.333 with N133 powder.
52 Berger FBs averaged 0.466 with N133 powder. (Can't explain why the Berger 52s did so poorly in this barrel. My CZ527 24-in barrel loved them.)
52 Nosler CCs averaged 0.367 with N133 powder.
52 SMKs averaged 0.343 with N133 powder.
52 Hornady V-Max averaged 0.363 with N133 powder.
53 SMKs averaged 0.376 with N133 powder.
55 Berger FBs averaged 0.343 with N133 powder.

My data shown above tells me that bullet weight, shape and length will determine what bullets your rifle will shoot best.
Bullet weight and powder combinations do seem to matter, however illogical that might seem.
Individual barrels are particular, and preferences will differ, even for equivalent barrel lengths - I have identical rifles with different preferences.
I have found that some powders just shoot better with particular bullets than others in particular barrels, and the same powder will perform better with a particular bullet weight compared to another bullet weight. regardless of the powder's burn rate.

The only way you will be able to determine what works for your barrel is to try different combinations of bullets and powders.
When you find several combinations that your rifle likes, shoot them most of the time.
I just was able to purchase some N540 and, to my surprise, it is getting better results than N140 and several other powders, using the same bullets that I have data for.
As a result, I will be experimenting more with N540, hoping that its performance will continue to shine.

Caution, my results might not transfer to your particular rifle - ever barrel is different.

Consider this - in a large rifle maker, a run of barrels on a particular day is made one after another.
(For a specialized barrel maker, a single barrel might be cut for each set up, but the reamer is reused until it is too worn to be reused, so the example below still holds.)
The barrel blank is of a particular lot of steel so the steel mix is the same, but the next lot will be very slightly different.
The barrel bore is cut using a reamer.
The reamer for the first barrel in the run is new and exactly the bore diameter.
By the time the last barrel bore in the run is cut, the reamer is slightly worn and the bore dimension is slightly smaller.
The same holds true for the reamer used to cut the chamber.
Now you see why no two barrels can be identical.

CFJunkie
06-10-2023, 09:19 AM
Unfortunately, you don't get to know what powder is being used in Factory ammo, so you will have to depend on the manufacturer to continue to use the same powder for as long as you shoot it.
I believe Federal used both Reloader 15 and IMR4064 powders at different times in their FGMM 168 grain .308 ammos so manufacturers may change powders depending upon availability and cost at times.

At least, when I run out of a powder and can't buy the same powder, I can note the difference and gather the data for the new combination.
And different powders obviously will produce different results with the same bullet.

The barrel will still tell you what it shoots best, manufacturer to manufacturer, at the same bullet weight. No two manufacturers will probably be using the same powder, even if they are using the same bullet.
Example, Federal GMM and Black Hills use Sierra SMK bullets in different bullet weights and Federal also makes FGGM with Nosler CCs (or at least they used to).

Whynot
06-10-2023, 01:17 PM
As a differing opinion to CFJunkie's post--

Unless you have a very specific reason/need to try all of that testing then I don't get it. The problem is that we tell people that "every barrel is different and they need to find the best load for your gun." But that's a never ending process because of how many different combinations of bullets/powders/primers/cases/neck tension/ seating depth etc. What you need to do is find a load that meets your needs and then use it. I have shooting friends that are always changing something and when shooting always say things like "my rifle isn't sighted in for this round- or I don't know the drop because of a charge change I made."

Calling .466 and .375 groups poor is just not a relatable thing for 99% of the shooters.... and leads the mindset that they have to do more load development to get their 3/4moa group down or they wont be able to hit anything. Especially considering that the original poster wanted to make hits at 300 yards..... I've taken wolf gold and Armscor 55 grain to 600 with good results- so no need to make is more difficult.

Turkeytider
06-10-2023, 02:17 PM
Pardon me in advanced for this long post, but I believe that the data will let you see that there is no easy answer for which bullet will perform best in your new barrel.

I believe that your rifle is telling you that it might shoot bullets in the 69 and maybe up to the 77-grain range better than the lighter bullets.
You might also try the Hornady 73 gr ELD-Ms or the 75 gr ELD-Ms. They aren't as expensive as the Berger, Nosler or Sierra heavy bullets.

Here is some data that might let you see how one particular rifle barrel performs with different powders and bullets, no matter how confusing and illogical it might seem.

The 73 gr ELD-Ms shoot more accurately in my Savage 12 FV rifle with a 26-in 1:9 twist barrel than the 75 ELD-Ms.
But my 1:9 twist consistently shoots 77 gr bullets accurately so the 75 gr bullet weight shouldn't have caused the difference.
The same 1:9 twist rifle shot 77 SMKs to a 0.235-in average for 10 5-round groups at 100 yards using N540 powder during my last session. (We'll see if N540 accuracy holds up for a larger sample.)
77 SMKs averaged 0.292-in average for 90 groups with IMR4166 powder, and 0.289-in average for 83 groups with N140 powder.
77 TMKs averaged 0.279-in average for 205 groups with IMR4166 powder, and 0.282-in average for 61 groups N140 powder.
77 Nosler CCs averaged 0.280-in groups for 12 groups with H4895 powder, and 0.227-in average for 9 groups with IMR4166 powder.
77 Berger OTMs averaged 0.282-in average for 17 groups with N140 powder.
73 ELD-Ms shot a 0.264-in average for 8 groups with H4895 powder and 0.273 for 7 groups with N140 powder a few months ago. (I need to find more of these.)
75 ELD-Ms shot 0.375-in average for 4 groups with N140 powder at about the same time. (I was surprised that the 75 ELD-Ms did so poorly.)
69 SMKs shot a 0.235-in average for 21 groups with N540 powder.
69 SMKs shot a 0.289-in average for 32 groups with N140 powder and a 0.292-in average for 93 groups with IMR4166 powder.
69 Nosler CCs shot a 0.310 average for 13 groups with IMR4166 powder.
69 RMR shot .0296-in average for 11 groups with N140 powder.
(2000 69 RMR bullets cost about the same as 500 SMKs so if you want a bargain heavy bullet that shoots pretty well, this might be your best bet.)

In comparison, lighter bullets didn't shoot as well in my Savage 12 FV.
50 gr Berger Varmint FBs averaged 0.390 with N133 powder.
52 gr Hornady ELD-Ms averaged 0.333 with N133 powder.
52 Berger FBs averaged 0.466 with N133 powder. (Can't explain why the Berger 52s did so poorly in this barrel. My CZ527 24-in barrel loved them.)
52 Nosler CCs averaged 0.367 with N133 powder.
52 SMKs averaged 0.343 with N133 powder.
52 Hornady V-Max averaged 0.363 with N133 powder.
53 SMKs averaged 0.376 with N133 powder.
55 Berger FBs averaged 0.343 with N133 powder.

My data shown above tells me that bullet weight, shape and length will determine what bullets your rifle will shoot best.
Bullet weight and powder combinations do seem to matter, however illogical that might seem.
Individual barrels are particular, and preferences will differ, even for equivalent barrel lengths - I have identical rifles with different preferences.
I have found that some powders just shoot better with particular bullets than others in particular barrels, and the same powder will perform better with a particular bullet weight compared to another bullet weight. regardless of the powder's burn rate.

The only way you will be able to determine what works for your barrel is to try different combinations of bullets and powders.
When you find several combinations that your rifle likes, shoot them most of the time.
I just was able to purchase some N540 and, to my surprise, it is getting better results than N140 and several other powders, using the same bullets that I have data for.
As a result, I will be experimenting more with N540, hoping that its performance will continue to shine.

Caution, my results might not transfer to your particular rifle - ever barrel is different.

Consider this - in a large rifle maker, a run of barrels on a particular day is made one after another.
(For a specialized barrel maker, a single barrel might be cut for each set up, but the reamer is reused until it is too worn to be reused, so the example below still holds.)
The barrel blank is of a particular lot of steel so the steel mix is the same, but the next lot will be very slightly different.
The barrel bore is cut using a reamer.
The reamer for the first barrel in the run is new and exactly the bore diameter.
By the time the last barrel bore in the run is cut, the reamer is slightly worn and the bore dimension is slightly smaller.
The same holds true for the reamer used to cut the chamber.
Now you see why no two barrels can be identical.

Thank you sir for taking the time and trouble to present so much information. I truly do appreciate it. I`m shooting factory loads, however. Next up will be Federal Gold Medal, 77 grain with SMK bullets. If I can get those to zero, I`ll have shooting information on two loads, the other being 68 grain Frontier ( Hornady ) OTMs. If the 77s shoot as I expect them to, I can look at a variety of offerings at 77 grains.

charlie b
06-10-2023, 05:00 PM
To be honest, never heard of " over stabilization " of a bullet. What does that do, if anything, to impact performance?

Short answer is it does not affect bullet performance in most cases and really only comes into play at very long range and/or large trajectories.

Over stabilization is when the projectile is spinning much faster than required for keeping it stable. The result is the nose of the bullet will not stay pointed in the direction of flight, ie, it will fly 'nose up'. You'd have to shoot at a much longer range to see any effects from this. The only time it is critical is in artillery when you need the nose of the projectile to hit with the nose at a specific angle to the target.

Turkeytider
06-10-2023, 06:39 PM
As a differing opinion to CFJunkie's post--

Unless you have a very specific reason/need to try all of that testing then I don't get it. The problem is that we tell people that "every barrel is different and they need to find the best load for your gun." But that's a never ending process because of how many different combinations of bullets/powders/primers/cases/neck tension/ seating depth etc. What you need to do is find a load that meets your needs and then use it. I have shooting friends that are always changing something and when shooting always say things like "my rifle isn't sighted in for this round- or I don't know the drop because of a charge change I made."

Calling .466 and .375 groups poor is just not a relatable thing for 99% of the shooters.... and leads the mindset that they have to do more load development to get their 3/4moa group down or they wont be able to hit anything. Especially considering that the original poster wanted to make hits at 300 yards..... I've taken wolf gold and Armscor 55 grain to 600 with good results- so no need to make is more difficult.

.466 and .375 groups? I`m going home a happy man! Especially considering I`m shooting factory loads. I guess I take a lot of pleasure in not being as demanding. I don`t think I`ll ever shoot good enough to get to the point of saying something like, " I`m so disgusted! A .5 MOA group! " . My only regret is probably not ever knowing just how good my guns might truly shoot by not hand loading.

Turkeytider
06-10-2023, 06:41 PM
Short answer is it does not affect bullet performance in most cases and really only comes into play at very long range and/or large trajectories.

Over stabilization is when the projectile is spinning much faster than required for keeping it stable. The result is the nose of the bullet will not stay pointed in the direction of flight, ie, it will fly 'nose up'. You'd have to shoot at a much longer range to see any effects from this. The only time it is critical is in artillery when you need the nose of the projectile to hit with the nose at a specific angle to the target.

Thanks Charlie. I can`t imagine what was happening with those 55`s . It was like a different gun with the 68`s.

charlie b
06-10-2023, 08:49 PM
Yeah, I had that kind of problem with light bullets in my Axis, but, not that bad. The factory 55gn loads just didn't do well for me. 2" and sometimes 3" groups were common. When I went to 69gn and then 77gn the rifle became much more accurate than I could shoot. Never bothered going back to try some premium 55gn bullets. The 77gn Sierra's were so accurate I bought them in bulk :)

The only problem is premium ammo is the expense :(

tomme boy
06-10-2023, 10:20 PM
Thanks Charlie. I can`t imagine what was happening with those 55`s . It was like a different gun with the 68`s.

It's from the junk Hornady ammo. They can make a bullet but the ammo is JUNK

Turkeytider
06-10-2023, 10:35 PM
It's from the junk Hornady ammo. They can make a bullet but the ammo is JUNK

My understanding is that the Frontier line of Hornady ammunition is manufactured at Lake City Arsenal which makes ammunition for the armed forces. They use Hornady bullets, unless all that`s changed.

Turkeytider
06-10-2023, 10:50 PM
I took a look at the back side of the target sheet. The holes left by the 55 grain bullets were markedly different from those of the 68 grain. While the 68`s were nice, regular round holes punched through, the 55`s were more irregular in shape with almost torn like edges. I think those bullets were different when they hit the target than when I first loaded them to shoot.

charlie b
06-10-2023, 11:30 PM
Well, the 'easy' answer is to use 69 and 77gn loads :) Not the cheapest, but, at least the targets will make you happy :)

Turkeytider
06-11-2023, 07:02 AM
Well, the 'easy' answer is to use 69 and 77gn loads :) Not the cheapest, but, at least the targets will make you happy :)

Yep, looks like that will be the way I`ll be going, at least with that gun. The 55`s will be for my 110 ( 1:9 )

charlie b
06-11-2023, 12:20 PM
You might try the 69's and 77's in the 110 as well :) I know the Axis liked them and it had a 1:9 twist with just a 22" barrel.

Turkeytider
06-11-2023, 12:32 PM
You might try the 69's and 77's in the 110 as well :) I know the Axis liked them and it had a 1:9 twist with just a 22" barrel.

Thanks Charlie, can`t hurt. Who knows? Might expand the use and capability of what I`ve considered primarily a hunting rifle, maybe more range applications(?).

tomme boy
06-12-2023, 01:19 AM
My understanding is that the Frontier line of Hornady ammunition is manufactured at Lake City Arsenal which makes ammunition for the armed forces. They use Hornady bullets, unless all that`s changed.
Frontier ammo has also been responsible for blowing up 50 or more rifles. But Hornady always says it is the guns fault. 1 or 2 rifles maybe but not the amount that was blown up a couple yeas ago.

The Critical Defense ammo was the only ammo I have had that had duds. Tore them apart and the 2 rounds did not have flash holes. How is that for carry ammo? I load my own now, screw them.