257 Ackley Improved. 80 grain Bullets an RL 19

[riflewoman]

I’m in the process of developing loads for a wild hog hunt. Planning to load the Barnes 80 grain TTSX solid bullets. Anybody have experiebpnce with RL 19? Other powders?


Thanks

 

[JRS]

Call Randy Robinett (BIB bullets). He knows what works in the 257 Ackley and what doesn't

 

[ShootDots]

It's been a L-O-N-G time since I shot a .257 Roberts A.I. However, I shot the 85 grain Nosler Ballistic Tip. The best powder I found was IMR 4831. I can't remember the exact charge but it was "in the vicinity" of 55 grains. The B-Tip was sailing out of a 26" barrel at 3550! It was very, very accurate! I shot a prairie dog, 1 shot, at 508 long paces! I also shot a crow, 1 shot, at 440 long paces! It just so happens that RL-19 and IMR 4831 are very close in burn rate. However, I believe that IMR 4831 is the better of the 2 powders as it burns very clean! I love IMR 4831! If it had short kernels, and was an "Extreme" powder, I would use it in place of H4350! It is slightly slower but it is like IMR 7828 in that it produces LOADS of velocity for whatever reason! Neither of those powders are a double based powder impregnated with Nitro!

 

[Shoebox]

257 ai 85 nbt
Rl 19 54 -58 max 25" 3500+ in old m70
Rl 17 works well in 2506 might be worth a look

 

[Kurz]

I happen to like this style of bullet for several cartridges and use them as a standard for some hunting loads.

Here is the book information from Nosler for a similar bullet. These published loads are certainly within the realm for testing and do not exceed what this combination is capable of producing. In addition, I've used two of the 'temp stable' powders, Re16 and Re-23 with good results. IMR-4831 and H100V both work well with the cooler burning 100V being a better choice for volume shooting. Norma URP should be included in the testing as its performance was excellent also.

 

[Zero333]

This may or may not help you. But I'll post it anyways.
=======================================

Cartridge : .257 Ack Imp (257 Rob)
Bullet : .257, 80, Barnes 'TTSX'BT 25731
Useable Case Capaci: 57.008 grain H2O = 3.701 cm³
Cartridge O.A.L. L6: 2.775 inch = 70.49 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Alliant Reloder-19

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-20.0 82 43.20 2730 1324 27559 8403 79.0 1.359
-18.0 84 44.28 2799 1392 29344 8726 80.6 1.327
-16.0 86 45.36 2869 1462 31251 9047 82.2 1.296
-14.0 88 46.44 2940 1535 33291 9365 83.7 1.265
-12.0 90 47.52 3011 1611 35471 9677 85.2 1.235
-10.0 92 48.60 3083 1688 37804 9984 86.6 1.206
-08.0 95 49.68 3155 1769 40302 10284 88.0 1.177
-06.0 97 50.76 3228 1851 42977 10576 89.4 1.148
-04.0 99 51.84 3302 1937 45847 10857 90.6 1.115
-02.0 101 52.92 3375 2024 48926 11128 91.8 1.083
+00.0 103 54.00 3450 2114 52232 11387 93.0 1.051 ! Near Maximum !
+02.0 105 55.08 3524 2206 55788 11633 94.0 1.019 ! Near Maximum !
+04.0 107 56.16 3599 2300 59617 11863 95.0 0.989 !DANGEROUS LOAD-DO NOT USE!
=======================================

So according to Quickload prediction...
54 gr of RL-19 generates 52,232 psi of pressure,,, 3,450 fps,,, 93% propellant burnt,,, 103% case fill (but not compressed).

Reduce - Work up - Be Safe - Have Fun !

 

[riflewoman]

Thanks very much Zero333. Gives me some good info to go on. It looks like, in this application, RL19 might be a hair faster than H4831. I’ll keep the group informed.

Thanks again.

 

[Brians356]

Someone on this forum once said RL-17 works very well in 257 AI. I'll try to recall who.

Looking at Sierra's data (26-in barrel) you should be able to get over 3500 from an 80-gr, using IMR-4350 or similar speed powders. You really should call Sierra and talk to Paul Box, their Ackley man. What he doesn't know about powders for the seven AI cartridges Sierra publishes data for ain't worth knowing. He was quite happy to chat about my 250 AI.
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[JRS]

Someone on this forum once said RL-17 works very well in 257 AI. I'll try to recall who.

Looking at Sierra's data (26-in barrel) you should be able to get over 3500 from an 80-gr, using IMR-4350 or similar speed powders. You really should call Sierra and talk to Paul Box, their Ackley man. What he doesn't know about powders for the seven AI cartridges Sierra publishes data for ain't worth knowing. He was quite happy to chat about my 250 AI.
-

RL-17 also works well in the 250 Ackley and 25x47

 

[Brians356]

RL-17 also works well in the 250 Ackley and 25x47

And, by extension, in the 25 Creedmoor, which is essentially just the 250 Ackley (30-deg).
-

 

[RGRobinett]

Though, via my 257 Ack. Imps., I always shoot 110 Gr. bullets, RL-17, at very safe pressure, delivers 200+ FPS over
every other powder tried: it's as if this powder was formulated for the 25 Cal. expansion ratio! That said, it may not shine quite so much with lighter bullet weights, but I'd bet on markedly higher velocity than the customary powders - presuming you're after all the V and precision you can get.

Since first availability, & my initial range session, RL-17 has been my go to .257 Ack. Imp. powder: 3330FPS with 110 Gr. BT, via 24" BBL. Stable/predictable precision & performance across temperatures from below freezing to above 90F. I'm always dismayed that the BIG boys list it only sparingly in their manuals . . . RG

 

[riflewoman]

Thanks. It’s definitely on the list to try. My rationale for the 80 grain bullets is the rifle has a 12 twist barrel. So the rifle won’t stabilize a 100 gr solid. And even then velocity is paramount. So, given the complete lack of data from Barnes et al, what powder have you found it to be comparable? My guess is 4350, but I wish I had some data.

 

[Brians356]

Though, via my 257 Ack. Imps., I always shoot 110 Gr. bullets, RL-17, at very safe pressure, delivers 200+ FPS over
every other powder tried: it's as if this powder was formulated for the 25 Cal. expansion ratio! That said, it may not shine quite so much with lighter bullet weights, but I'd bet on markedly higher velocity than the customary powders - presuming you're after all the V and precision you can get.

Since first availability, & my initial range session, RL-17 has been my go to .257 Ack. Imp. powder: 3330FPS with 110 Gr. BT, via 24" BBL. Stable/predictable precision & performance across temperatures from below freezing to above 90F. I'm always dismayed that the BIG boys list it only sparingly in their manuals . . . RG

Yes, e.g. Sierra tests RL-15 a lot, but seems to neglect RL-17. I asked Paul Box about RL-17 in 250 AI, he said sure, it's a good powder for that cartridge, but in his testing, anyway, RL-15 was superior across the board.

I would think RL-15 might shine brighter in 257 AI for the lighter bullets, e.g. the 80-gr., but Sierra shows RL-15 is down 100-fps in velocity from max w/ 75-gr pill, yet lists RL-15 equal to 4 other powders for top velocity behind 87/90-gr pills. I sure think RL-17 is worth a try in any case, based on your experience.
-

 

[RGRobinett]

Thanks. It’s definitely on the list to try. My rationale for the 80 grain bullets is the rifle has a 12 twist barrel. So the rifle won’t stabilize a 100 gr solid. And even then velocity is paramount. So, given the complete lack of data from Barnes et al, what powder have you found it to be comparable? My guess is 4350, but I wish I had some data.

When introduced, Alliant's advertising stated that the burn rate is similar to 4350, but, where applicable, RL-17 could produce 200+FPS higher MV than can/could be expected with more traditional (my wording here) powders: the 4350s; RL-19;H-4831; etc. Prior to my initial range visit with RL-17, I was a skeptic - believed, that once again, I'd been duped by the hype! However, the results of that first trial have stood up to time and displayed, that Via .25 Cal. cartridges, with capacities from .250/300 Ac. Imp./25x47 LAPUA, up to, at least 25/06, RL-17 delivers as promised.

It also delivers sterling precision and velocity via the 22BR with 72 - 75 Gr. bullets, and my .220Ack. Swift barrels. Via the latter, only another 150 FPS or so - not quite as spectacular as via the .25 cals. With light [25cal.] bullets, it may not deliver any better that the .220Ack. Swift model.

Presuming you already have the barrel, your bullet choice is probably good - I do not know the length of the Barnes 80 Gr., & whether it's a BT, or FB - a SWAG is that it's about as long a bullet as a 1:12" twist will handle. If the copper bullet is 0.97" long (a wild guess), the specific gravity of construction will be about 9.1 (longer will be lower/worse) . . . at sea-level, Std conditions, and 3500 FPS, a twist rate of 1:11.2" would produce Sg 1.5 - for this length, a 12" twist will probably still work ok, producing somewhere between Sg 1.3 & 1.4.

If the bullets are 1.0"long, the picture changes somewhat: specific gravity of construction would be only 8.8, and twist requirement for Sg 1.5 would be 1:10.6" - 1:12" twist could prove shakey. All wild ass guesses here, but stuff to consider - I did the calculations based upon a BT - a FB would, for a given twist/velocity, increase the Sg.

The specific gravity of construction relates to the balance point, thus the effect of the overturning moment: copper bullets and polymer tips make long for weight projectiles - that's why the lighter weight bullets are marketed by the manufacturers of monolithic bullets. I cannot argue against their effectiveness on game - that is not my intent. It pays to know the territory B4 investing in custom barrels, etc.

Not wanting to be a smart-ass naysayer here, just hoping to help others understand B4 taking a plunge into unknown waters. RG

 

[Brians356]

When introduced, Alliant's advertising stated that the burn rate is similar to 4350, but, where applicable, RL-17 could produce 200+FPS higher MV than can/could be expected with more traditional (my wording here) powders: the 4350s; RL-19;H-4831; etc. Prior to my initial range visit with RL-17, I was a skeptic - believed, that once again, I'd been duped by the hype! However, the results of that first trial have stood up to time and displayed, that Via .25 Cal. cartridges, with capacities from .250/300 Ac. Imp./25x47 LAPUA, up to, at least 25/06, RL-17 delivers as promised.

RL-17 seems to be Alliant's answer to Hodgdon Superformance WRT velocity anyway.
-

 

[RGRobinett]

RL-17 seems to be Alliant's answer to Hodgdon Superformance WRT velocity anyway.
-

Roger the Superformance - another under-hyped, under used, but very good performer. I won't [yet] reveal the velocity I achieved via H-Superformance and 138 Gr. BT, via my latest .257 Ack. Imp. barrel - a 24", 1:8" twist, 4-groove, Bartlein. Have yet to try the RL-17 with the 138s - only had time for one brief range session, which showed promise. H-Superformance has been great stuff, for the .257IdiotMag (.25/300WSM): 110 Gr. BT at 3540 &, again, well short of case-wrecking pressure. Can't recall which came first - probably the Superformance, asit was one of the first powders we tried in the .257 IdiotMag, for which Hugh Henriksen made a reamer as soon as Win. spec'd the .300WSM - that's been a great coyote, pronghorn, and mule deer slayer . . . but, so is a .257 Wby.! RG

 

[Brians356]

Roger the Superformance - another under-hyped, under used, but very good performer. I won't [yet] reveal the velocity I achieved via H-Superformance and 138 Gr. BT, via my latest .257 Ack. Imp. barrel - a 24", 1:8" twist, 4-groove, Bartlein. Have yet to try the RL-17 with the 138s - only had time for one brief range session, which showed promise. H-Superformance has been great stuff, for the .257IdiotMag (.25/300WSM): 110 Gr. BT at 3540 &, again, well short of case-wrecking pressure. Can't recall which came first - probably the Superformance, asit was one of the first powders we tried in the .257 IdiotMag, for which Hugh Henriksen made a reamer as soon as Win. spec'd the .300WSM - that's been a great coyote, pronghorn, and mule deer slayer . . . but, so is a .257 Wby.! RG

A cursory search for old references indicate both Superformance and Reloder 17 appeared in 2008. So one is probably not a response to the other, but rather a happy coincidence.

Another overachiever powder is CFE 223. For the cartridges Hodgdon publish CFE data, it is often either tops in velocity, or a close 2nd place (not unusually behind Superformance.)
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[JRS]

Barnes actually lists data for it, but with a 1:10 twist barrel.

 

[Barlow]

257AI, 25" Rock Creek 9 twist. 51.5gr rl17, 87 gr Hornady, 3613mv. 48.5gr rl17, 100gr Hornady, 3270mv. 49gr rl17, 117gr Hornady, 2940mv. I think I could safely get more speed as there were no pressure signs, but these loads are 1/2 moa in my rifle, and absolutely no more velocity is needed. RL17 is magic powder in this rifle. As always start low. Barlow

 

[Kurz]

I've read quite a little bit regarding Re-17 including all the naysayers 'reports' of being temp sensitive. It makes me happy to read some of the comments above because they seemingly validate what I've found through several years of shooting Re-17. I burn a lot of Re-17 from sea level to 9,000 feet. Also included here are Brian's positive comments about CFE223 and Superformance. As I also stated, I happen to like the various versions of the TTSX bullets for hunting, especially where the velocities can get to be fairly high with WSM, SAUM, RUM, Weatherby and others. But since everyone seems to think that the stability calculator is the absolute end all for determining twist rate and stability, I ran those numbers just to see what it produced:



This is based on my loads working around 3,800 fps in my 26" barrel. Yes, I have these bullets in stock and have shot them. I'm working from my notes.

Rather than throw yourself off a tall building after reading this, bear in mind that they are simply stating that the bullet will not 'Optimize' the stated BC from the manufacturer. If you run your tables using the lesser BC, your point of impact should be relatively close or as close as you are capable of resolving. Shoot your drop table.

Since you are favoring this bullet, get a short selection of the powders mentioned above and start you testing. Pay close attention to the geography of your hunting turf. If 300 yards is a long shot, work with those numbers. The BC quoted above should get you to 350-400 allowing for 1,000 ft/lbs of energy at the target.

Enjoy the process!