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Discussion Starter · #1 · (Edited)
loaded several rounds in different weights using once fired hornady brass, used 450 primers, cases trimmed to 1.676 and OAL 2.80--test bed is a 6.8 ARP barrel, ARP superbolt, one of semi-cops bolt carriers, Mega Arms upper/handguard and lower, A2 stock, CPD magazine

first i fired a baseline using S&B green box 110 gr FMJ, factory ammo. ran flawlessly, no FTF and bolt lock back on last round

1. 2670
2. 2710
3. 2689
4, 2711
5. 2674
6. 2683
7. 2668

then tested the CFE BLK

26.0gr, hornady 110 gr BTHP

1. 2559
2. 2558
3. 2561
4. 2580

rifle would not run, lock back the bolt, extraction functioned but FTF

26.4 gr

1. 2587
2. 2603
3. 2593
4. 2567.
5. 2620

good extraction, FTF

26.8

1. 2641
2. 2665
3. 2646
4. 2627
5. 2660

results same as above, good extraction, FTF

27.1

1. 2651
2. 2685
3. 2680.
4. 2700
5. 2683

same results on extraction and FTF

27.4 gr

1.2693
2.2703

same results on extraction and FTF

27.7 gr

1. 2726
2 2734

good extraction and continued FTF

28.0 gr

1. 2767
2. 2755

extracts but FTF

28.5 gr

1. 2773
2. 2797

extraction good, FTF

all the while i had been opening up the syrac gas block from the functioning baseline, finally had it full open and still using the same magazine i ran the remainder of the S&B, gun ran flawlessly but recoil was much higher LOL

soooo, for some reason the CFE BLK will not run in this rifle. accuracy (which was not the reason i was there, was satisfactory for the conditions today, 20mph straight in the face wind, gusting to 30

2" painter's tape for aiming, one's on the low left outside the tape was getting the scope zero'd. first pic is all the S&B and the CFE BLK firing the 26 grain loads, the second pic is the 27 and 28 grain loads



 

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Discussion Starter · #3 ·
Crayj, what barrel length are you running? I've had great results with this powder in x39, and will try it in 6.8.
18" midweight ARP. good to hear it works for the X39, perhaps if i was using a carbine buffer and stock it might run ok, spoke with Mr. Beene and i'll drill the gas port with a #43 bit
 

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Tried CFE BLK yesterday in my 16" ARP 5R with surprising results. Worked up to 28 gr at 2.285" in S&B cases with 450 primers and 110 HPBT. This was my most promising load with 2705 fps average, and just under 1" groups. I was shooting off my 4 wheeler rack, so my rest was not optimal.

I'm sure I can do better from a bench, but those numbers are encouraging, especially from a 16" barrel.
 

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Discussion Starter · #5 ·
28 gr in my 18" barrel gave slightly over 2750, and the brass showed no pressure signs, how about your brass?
 

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28 gr in my 18" barrel gave slightly over 2750, and the brass showed no pressure signs, how about your brass?
Brass was fine. Looking at Hodgdons data, it doesn't seem like this kind of performance is possible, but I'm highly impressed with it. Once I got over the SAAMI charge weights, velocity picked up big time. Now I'm gonna play with OAL and see what happens.
 

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Discussion Starter · #7 ·
enlarged the gas port with #43 bit, finally had some good weather and fired it this morning. used the 27.4 load in the above trials. had the syrac open 6 clicks, and the bolt locked back, dropped down to 5 and it would not lock back, set on 7 and fired several more rounds, lock back every time. now i have several barrels to enlarge the port as my goal is to end up using just 2 powders, CFE 223, and CFE BLK, those will work in the 4 calibers i currently load
 

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Cfe blk & 90 tnt

I loaded a few with the BLK yesterday to try. On Hodgdon web page they showed load data for the 90gr bullet, so why not. Started with 27 gr and ended with 30.1, the max on the web site. Currently loading 31.7 gr of H322; which gives me 2,880 FPS and 1/2 MOA from my 20" ARP barrel. With only 30.1 gr CFE BLK, CCI #41 primers, and used Hornady brass I saw 3,008 FPS and 2,999 FPS with only faint swipes on the brass. When I loaded one with new brass the velocity jumped to 3,050 FPS WOW!!!! Is it common to gain velocity with new brass? I will try and get to the range on Wednesday or Thursday to shoot a group with the CFE BLK. The CFE BLK works great with my RCBS dropper, and takes less case capacity. I like what I have seen so far. If it groups well I will be headed to the store for a big can lol.
 

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View attachment 29601

CFE BLK UPDATE:

I ran a string of five over the chronograph and here are the results.

Keep in mind the three shot group (100 yds) from earlier today was about half a minute and each charge was trickled/weighed.

The five rounds I prepped for the chronograph test was using my rcbs uniflow and were not weighed after it was set to throw 26 grains. That five shot group opened up a bit but still came in shy an inch.

Hornady brass, Federal GMAR primer, 110 BTHP seated to cannelure, coal=2.258"

View attachment 29593
 

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90 Grain TNT & CFE BLK

Ran a test on 31.1 grains of CFE BLK and the 90 grain TNT bullet set to 2.290 C.O.A.L. in multi-fired Federal brass popped by Remington 7 1/2 primers.

Shot through an 18 inch ARP barrel with 3 groove 1-12 inch twist barrel.

.32 inch group with 6 shots at 50 yards.

Velocity: 2990 FPS average. Standard Deviation: 25 FPS.

Only a very slight ejector swipe.

Daniel
 

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Another Load Test with 90 grain TNT & CFE BLK

Ran a test on 30.5 grains of CFE BLK and the 90 grain TNT bullet set to 2.290 C.O.A.L. in multi-fired Federal brass popped by Remington 7 1/2 primers.

Shot through an 18 inch ARP barrel with 3 groove 1-12 inch twist barrel.

.466 inch group with 5 shots at 50 yards.

Velocity: 2952 FPS average. Standard Deviation: 232 FPS.

No ejector swipe.

Daniel
 

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Ran a test on 30.5 grains of CFE BLK and the 90 grain TNT bullet set to 2.290 C.O.A.L. in multi-fired Federal brass popped by Remington 7 1/2 primers.

Shot through an 18 inch ARP barrel with 3 groove 1-12 inch twist barrel.

.466 inch group with 5 shots at 50 yards.

Velocity: 2952 FPS average. Standard Deviation: 232 FPS.

No ejector swipe.

Daniel
SD of 232???????
 

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I was waiting.

SD of 232???????
I was waiting for someone to catch that one. You can join the team now. It was 32 FPS Standard Deviation (SD).

Daniel
 

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Guys, this powder is great and accuracy and speed are good, but for the life of me I can't get the bolt to lock back no matter the charge nor adjustment on my gas block.

im trying on 110gr AB, tried 115gr smk, and 120gr SST.

any suggestions?
 

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Discussion Starter · #20 ·
Guys, this powder is great and accuracy and speed are good, but for the life of me I can't get the bolt to lock back no matter the charge nor adjustment on my gas block.

im trying on 110gr AB, tried 115gr smk, and 120gr SST.

any suggestions?
i use ARP barrels for nearly everything, only rounds i loaded were in 6.8, i had to enlarge the barrel gas port to a #43 wire, they all run fine now and my adj blocks are set at 5-6 clicks open. next i'll load some x39 up. if i can get things going my way i'll end up using just 2 powders, cfe 223 and blk. i used 110gr hornady hpbt, heavier bullets i would likely consider 223 instead of blk
 
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