6.5 PRC: ELD-M vs ELD-X Chrony Test, Factory loads

[frank320]

I was at the 300 yd range yesterday and shot both bullets under identical conditions.
According to Hornady, using the same rifle, the ELD-X should be 50fps faster than ELD-M.
But the ELD-X was shooting almost 200fps faster.

According to Hornady(with 24 inch barrel):
ELD-M: 2910fps/2764 ft lbs
ELD-X: 2960fps/2782 ft lbs

Here are yesterday's Chrony numbers(Masterpiece Arms, 26 inch Proof Barrel, 1:8 twist, 60F, 90% humidty), 700ft elevation:
ELD-M: Averaging 2850fps/2655 ft lbs
ELD-X: Averaging 3040fps/2936 ft lbs

I had expected the ELD-M to shoot around 2950fps or more. According to Hornday, both ELD-M/X should be hitting 2760+ft lbs with 24 inch barrel. But yesterday, the ELD-M was only hitting 2650 ft lbs while the ELD-X was hitting 2950 ft lbs under identical conditions.

With a 26 inch barrel, the ELD-X was right where it should be, but the ELD-M was way short. Accuracy/groups-wise, they were about 1.5inches at 300 yds, with the ELD-X grouping slightly better. And the muzzle brake blast and recoil from the ELD-X was definitely more than the ELD-Ms.

Maybe I got a bad batch of Hornday 6.5 PRC ELD-Ms?

Thoughts anyone?

 

[wade2big]

I shoot quite a bit of Hornady 6.5 creedmoor stuff. From their American gunner to the ELD-m. It is all slow. Good stuff, just slow. Its all holdovers or dialing anyways. If you don’t know the distance is 725 yards, the shooter will probably miss with 3040 or the 2850 that you posted.

 

[b6graham]

id use a real chronograph first.

the eldx seems right or slightly hot compared to other data i've seen. the 147s seem slow

 

[frank320]

id use a real chronograph first.

the eldx seems right or slightly hot compared to other data i've seen. the 147s seem slow

I am using a Caldwell G2 Chronograph for above posted data, 1.5 yards in front of muzzle.
Given that I am getting "spot on" data for the 6.5 PRC ELD-X, either Hornady's published data for the 6.5 PRC ELD-Ms are way optimistic, or I just have a bad batch of ELD-Ms.

Weird that the ELD-Xs are spot on though. and maybe even above Hornady's published data.

 

[b6graham]

should be 10-15' in front of muzzle per manual so that may be causing some of the issue whether flash or it's just reading weird

real chrono meaning labradar or magnetospeed v3/sporter

 

[frank320]

Chrono reading weird consistently for ELD-Ms only, but always spot on for ELD-Xs?

I really doubt it, because the Chrono strings were all 3 shot strings repeated alternatively between ELD-Xs and ELD-Ms and the extreme spread for all the grouped 3-shot strings were all within +-20fps(consistent) - 8 different 3-shot strings, 4 groups of 3-shot groups for ELD-X and 4 groups of 3-shot groups of ELD-Ms, groups shot alternately.

 

[D2junky]

My load development for the ELDX started and ended with the Precision Hunter Factory ammo. For this year at least. I don’t know that I could load much better for my Proof prefit/TL3 or my Impact Stuteville. It was the only thing available locally and I bought every last box.

 

[frank320]

My load development for the ELDX started and ended with the Precision Hunter Factory ammo. For this year at least. I don’t know that I could load much better for my Proof prefit/TL3 or my Impact Stuteville. It was the only thing available locally and I bought every last box.

Yes, they seem to have ran out of 6.5 PRC 147gr ELD-Ms. Only 143 gr ELD-Xs are availble. Can't find ELD-Ms anywhere. I bought my batch of 147gr ELD-Ms about 6 months ago. Running a little low on supply of my ELD-Ms 2 weeks ago, hence bought a case of ELD-Xs a week ago to test, and was surprised by the results above.

Maybe Hornady found out the initial batches 6.5 PRC 147 gr ELD-Ms were under-performing, and the new upcoming batch might get performance boosted? 6 months ago, ELD-Ms were available, but ELD-Xs were not. Then suddenly, the new ELD-Xs batch I shot this weekend were all hot and spot on performance-wise.

 

[b6graham]

maybe the 147s have some weird flash thats being effected by the chrono being close. could be same thing picking up 143s faster thinking its further idk

you never mentioned ES/SD, not that 3 rounds means anything in that department. not sure what you mean +- 20fps. thats a big change in average speed on same day, unless youre also talking cold clean barrel to end of day warm barrel

whatever it is. if you go back and confirm those speeds, thats just what it happens to be in your gun, but i'd say hornady seems to be pretty good about posted speeds

or you have a slow lot of 147s and a fast lot of 143 and thats all it is. as long as you know speed and dope theyll both shoot very well to distance and with decent energy but id probably pick the 143 in this case

 

[frank320]

you never mentioned ES/SD, not that 3 rounds means anything in that department. not sure what you mean +- 20fps. thats a big change in average speed on same day, unless youre also talking cold clean barrel to end of day warm barrel

For ELD-Ms, 4 X 3-shot groups(12 rounds) Averaging 2850fps, low=2835, high=2868, sd=12.3
For ELD-Xs: 4 X 3-shot groups(12 rounds) Averaging 3040fps, low=3032, high=3065, sd=9.5

3-shot group of ELD-M and ELD-X shot alternatively with ELD-M going first then ELD-X, order changed the next time around after barrel is allowed to cool down. ELD-X always about 200fps faster regardless.

 

[b6graham]

ruling out chrono distance, id guess just slow 147s being old and fastish 143s being new. ES/SD look right

 

[Aaron47pb]

Does having a bullet jammed affect velocity? If so, maybe the 147s are jammed in your chamber and the 143s aren’t.

 

[b6graham]

Does having a bullet jammed affect velocity? If so, maybe the 147s are jammed in your chamber and the 143s aren’t.

jammed typically results in more speed, not less.

 

[Dooby]

I don't have experience with the 143 ELD-X, but i have 2 diff lots of the 147 ELD-M Factory ammo. One lot is slower and initially only getting ~2830fps out of a 24" new factory rifle barrel. That barrel took ~200rnds to break in and the slow lot is now hitting around ~2920fps. The Fast lot, i get roughly ~2960+fps. ES and SD's are in the teens usually (if my shooting posture/position and shouldering the rifle firmly).

With my pre-fit/custom barrel, 22", after broken in (took only ~50rnds), slow lot showed ~2925fps. the Chamber on my factory rifle is a bit on the loose side. the 22" PVA barrel has a pretty tight chamber, HeadSpace only grew 0.001".

how many rounds do you have through your barrel? factory barrel or custom (pre-fit?).

 

[frank320]

I have about 120 rds thru it, mostly 147 gr ELD-Ms. The barrel is a Proof Research Carbon 26 inch barrel, chambered and fitted by MPA. Rifle was ordered as from MPA - MPA Hybrid Hunter 6.5 PRC. The rifle is accurate and consistent as hell, more accurate than I can shoot it. Just weird how I am getting such a huge speed difference between the ELD-M vs ELD-X....

 

[db2000]

Christiansen Arms MPR 6.5 PRC 24” carbon barrel 1-8” SilencerCo ASR flash hider
2019-2020 Magneto v3 chrono

37F, 37% humdity, 30.20mmHg, 800 ft elevation

Factory Ammo
Hornady Precision Hunter
143 gr ELD-X
3007, 3040, 3055, 3033, 3059 SD 20.7 cold, clean barrel
3060, 3056, 3028, 3055, 3041, 3042, 3037, 3043, 3046, 3041
3042, 3041, 3046, 3033, 3014 SD 11.3 warm, dirty barrel

Factory Ammo
Hornady Match
147 gr ELD-M
3034, 3062, 3091, 3050, 3065
3076, 3047, 3065, 3064 SD 21.0 cool, clean barrel

 

[Dj907]

147gr. ELD-M getting 3034fps out of a 26” bartlein 1-7.5 twist ??