6.5 CM: 135 gn A-Tip vs AR Hybrid 130s

[christopher.dow]

One of the things I learned at the Hide Cup 2019 is that my barrel is shot. I knew it was close, and had a new one on hand, but worried that changing right before the match would cause problems. Oh well. I'd already gotten a replacement barrel, and since the A-Tips had come out, I thought I'd try them and if I liked them, have that be the go-to bullet for this barrel. I've been using Berger AR Hybrid OTM Tactical 130s in the previous barrel.

The A-Tips come in a nice package:

Before starting load work up, I decided to take some measurements:

For purposes of searching, here's the data in text form:
AR Hybrid OTM (25 bullets):
Weight: 130 gn ave, ES 0.30 gn, SD 0.10 gn
Length: 1.316 in ave, ES 0.011 in, SD 0.003 in
BtoO: 0.719 in ave, ES 0.003 in , SD 0.001 in

A-Tip (25 bullets):
Weight: 135.05 gn ave, ES 0.20 gn, SD 0.07 gn
Length: 1.387 in ave, 0.002 ES, 0.001 SD
BtoO: 0.724 in ave, 0.002 ES, 0.000 SD

NB: I use three decimal places for linear measurements because most of our instruments are no better than that. The actual SD of the BtoO for the A-Tips was 0.0004...

First, the A-Tips are clearly super consistent. Not as consistent as Warners, which have no variance in any measurement my instruments can measure, but they're also a LOT less expensive.

The A-Tips are $0.75 vs $0.50 for the AR Hybrids. Using the mil wind formula, the AR Hybrids at 2850 give me a 6 MPH gun, as do the A-Tips, but the A-Tips have the 0.1 mil jump at 1000 yds, vs 700 for the AR Hybrids. That's pretty useful.

Hornady's load data gives me confidence I can get to 2850 with the A-Tips without problems, assuming I can achieve accuracy loading the A-Tips at 2.830 OAL like I do the AR Hybrids. They list max at 42.8 gn of RE-16 @ 2.815 OAL. I use averages like in the table above to get OAL from BtoO when I'm seating, so while I go by OAL, what I really use is BtoO.

The other considerations I have for this are availability of loaded ammo (AFAICT, Prime's new 130gn load is almost exactly my hand load with the same bullet apparently & it seems likely that Hornady will release a load based on the A-Tip), and then there's the 4DOF software and new Kestrel. If those make it so I don't have to true, I may switch to the A-Tip.

I'll do some experiments and report back.

 

[clcustom1911]

I Just did a load development series with the 130g Norma Golden Target (using what I got before going to 130 Hybrids), Prime Brass, FED210m, and Reloder 16. I found R16 fills the case very well and gives fantastic numbers.

Good luck and enjoy.

 

[christopher.dow]

I keep hearing good things about Reloader 16. It seems easier to get than H4350, too.

 

[clcustom1911]

I'm getting about ~2900 out of a 24" Proof Carbon, 4 groove. 42.1, 42.3, and 42.5 gave an average of .6MOA and single digit SD's and sub 20 ES for across all 3 charge weights. Case fill was probably just under 100% because there were a couple "crunch" sounds as I seated the rounds. COAL was the factory length of Proof ammo: 2.775" which gives .020" jump. .003" neck tension.

Obviously these are my loads, so, don't copy directly. Work up to them.

Alliant's listed max is 44gr.

Alliant Reloder 16 Data

 

[Steel head]

I keep hearing good things about Reloader 16. It seems easier to get than H4350, too.

I hear the same talk.

I’m almost out of 4451 and bought a pound of R16 to try out in my 260
I’ll try it against some H4350 to see if I get better performance than 4451.

 

[JMGlasgow]

One thing I've noticed with RL16 is it's dirty when using a suppressor. Lots of build up quickly. Haven't dealt with a carbon ring yet though.

 

[DarinC]

To 16 is my go to in my creed. Very good speed and single digit sd’s. Very little experience with cans though, so no input there.

 

[christopher.dow]

I'm getting about ~2900 out of a 24" Proof Carbon, 4 groove. 42.1, 42.3, and 42.5 gave an average of .6MOA and single digit SD's and sub 20 ES for across all 3 charge weights. Case fill was probably just under 100% because there were a couple "crunch" sounds as I seated the rounds. COAL was the factory length of Proof ammo: 2.775" which gives .020" jump. .003" neck tension.

Obviously these are my loads, so, don't copy directly. Work up to them.

Alliant's listed max is 44gr.

Alliant Reloder 16 Data

It's good to know that speed is achievable. I'll do a work up and try to get there.

 

[DarinC]

I’ve been able to push 130’s to 3k in my 24” bergara where pressure signs just start. So I’d say 2900 out of the 135’s should be safe with it.

 

[2aBaC̶a̶]

Im close to 2800 out of a 22" with 44gr of RL16 and a 140eld.

It gets crunchy around 44.5

 

[Diver160651]

I used RL powders for years in my hunting guns... and used to in a 308.. I agree, the powders seemed to run consistent SDs; at least with RL15 & RL22 I used to use.

One of the serious drawbacks to the type of powder, unless the formulas have changed, is temperature sensitivity. At least for me, I needed to have a summer load and winter hunting load.

Maybe things have changed with the powder, if so great. If not, just be careful running on the very edge of pressure, if you developed the load in cooler conditions.

 

[DarinC]

The new ones (16 and supposedly 26) are very stable in my experience. Actually speeding up 20 ish FPS at about 25 degrees vs original load development at 80 degrees. I haven’t played with 26 yet due to time, so we’ll see if it holds true with it as well