Posts: 22
Threads: 7
Joined: Jan 2021
Hi All. I went out yesterday in the afternoon in SE Louisiana and it was 93 out(damn hot and humid). Wanted to run through some Hornady Black, for the brass, and had 50 rnds of resized Starline brass to fire form using cheap 100gr bullets(picked up 500 pulled bullets). First cold bore shot with the Black was 2921fps. It settled down to 2875. They seem to running quite hot, so I surmise the powder is quite heat sensitive. The primers Hornady uses were all flattened. On some of the Hornady brass, the belt line is visible. Basically, I ordered what I could just for the brass. I am thinking about pulling all I have left and reducing the charge(do an OCW) or replacing it with LVR. All of the 50 resized Starline case looked great. They all measure 1.190" at the Datum. Every last one of them. At least I have my chamber now for them. The Hornady came in at 1.190" for only one case with a few at 1.191" and the rest at mostly 1.192" and one at 1.193". Go figure.
Time to clean, inspect, anneal and run them thru the dies. Any of y'all seeing high fps with the black? Oh, the barrel is a 24" McGowen.
Posts: 549
Threads: 54
Joined: Jan 2021
Think you are on the right track. Only other thing you may consider trying is to simply seat the bullets deeper to increase the jump to the lands. This may or may not make a real difference in your pressures. Depends how far the factory loads are from your lands as to if you are likely to experience a pressure decrease.
Posts: 399
Threads: 35
Joined: Jun 2020
The Hornady Black uses either CFE223 or Lever so yes, it's going to be quite temp sensitive. I've found the former to be >2fps/degree once it hits the mid 90s. Was your cold bore a clean bore? A clean bore will always run a tad faster until it gets fouled.
#FJB
Posts: 339
Threads: 38
Joined: Sep 2020
The fact that your Hornady Black cases are longer than your Starline cases, and along with flattened primers, it sure sounds like they were runnin' hot. Have you shot the same ammo in cooler weather with lower pressure signs? What's the CBTO length of your Hornady Black cases? Could the bullets be going up into the barrel lands? IIRC, there was an issue with the first batches of Hornady ammo jamming into the lands. Newer batches have a shorter CBTO...
The trick is growing up without growing old. -- Casey Stengal
Posts: 22
Threads: 7
Joined: Jan 2021
(07-24-2021, 03:16 PM)Old Bob Wrote: The fact that your Hornady Black cases are longer than your Starline cases, and along with flattened primers, it sure sounds like they were runnin' hot. Have you shot the same ammo in cooler weather with lower pressure signs? What's the CBTO length of your Hornady Black cases? Could the bullets be going up into the barrel lands? IIRC, there was an issue with the first batches of Hornady ammo jamming into the lands. Newer batches have a shorter CBTO...
Cooler weather in SE La this time of year??? Was thinking as they were hot, they would lengthen a little more. The bullets are not in the lands and it was a clean bore. They are .015" off. I measured them. The first 6 I shot, a few weeks ago, I did not have the chrono on. Just trying out on my 50 yard range out back to get the scope sited in a little. I think these things are just hot to begin with. I somewhere they are compressed loads. I did some 105 Barnes MBs and hit 2815 with 29.1 gr of LVR and they were .015" off the lands. They grouped way better than Blacks. Load was not even close to compressed but on the edge due to slight ejector marks and the BR41 primers were starting to flatten. I think they were running a little hot and backing them back down to 28.8gr for accuracy testing. I am pretty much decided to pull the blacks and downgrade the charge. I weighed the charge on one I had pulled to test the CBTO and it was a little over 30grs. May have to drop it back down to 29. Hmmm. I will post the results.
Posts: 549
Threads: 54
Joined: Jan 2021
Personally id still consider try compressing the load a bit more & seat 5 rounds .015" deeper for a test, may also wish to keep your ammo in a iced down cooler, up to just,prior to firing as well.
Just seems like less trouble than pulling bullets. Removing the packed in compressed powder that tends to be sticky & difficult to manage. then see if that powder in question meters well for your own reloads. Sounds like you are primary just after the brass if I understand correctly.
Otherwise Id look at pulling bullets & seating a lighter bullet with the same charge if I understand your goal here is primarily to acquire a brass supply.
I had considered something similar in the past & after removing powder from one cartridge I abandoned the idea of re-measuring an alternate charge of the original powder. Your milage may vary.
Posts: 365
Threads: 35
Joined: Jul 2020
I had 4 boxes of Black that were hot from the factory, same batch number. I chrono'd them. After shooting two boxes of them I took the last two boxes and shot them in my bolt gun. And like you I was seeing very high FPS in upper 2800 to low 2900. When I first starting loading this round I dissected a factory load and measured the powder to be 27.5 gn of what ever they load them with. Some folks say they load with CFE 223 or Lever, and it does look a lot like Lever. But ammo companies do not generally load with consumer grade powders, they have their own formulas.
I to was experiencing swipes and flattened primers as well. The bad part is I don't remember if they were from the recalled batch of ammo they loaded to long, I did have quite a lot of it that I had to reseat the bullets.
If you can not see the tyranny of having a gun ban enforced by men with guns... Then you fail to understand why the second amendment was written in the first place.
Posts: 5
Threads: 1
Joined: Jun 2021
Yeah, I had wondered if my chrono data I recorded was correct, seeing this finally makes me believe it.
Hornady 105's 20 rounds
2696 average, 2841 high
compared to factory 108s:
2621 average, 2969 high
and hand loads of CFE223
115gr berger target 29gr: 2580
112gr match burners 29gr: 2604
110gr SMK 29gr: 2592
Posts: 22
Threads: 7
Joined: Jan 2021
Hornady responded to a msg I sent on their FB page and wanted lot numbers. Talked to him over the phone. Nice guy. He wanted to know the FPS and he realized it was high. Offered to take the ammo, but just told him I was going to pull them and develop a lower charge. Told him with just 28.9gr of LVR and a 105 Barnes Match Burner, I got 2815fps. He stated they were getting 2707 to 2750 in their test barrels. Just so they know they got another lot which may be over charged. Maybe it is good for a bolt gun, but gas, no way. Left it a that. Will fire one of the other lot number(I have 5 boxes of it) and see if it does the same. Probably end of pulling it just to standardize the loads. Asked about the primers severely flattening and they are just normal bench rest so do not go by this when looking for over charging signs. I figured this much. I use BR41s. Y'all have a good day. Oh, on the two worst cases, you can see the case head/webbing line. I won't be firing these again.
Posts: 339
Threads: 38
Joined: Sep 2020
KenC...
What is the lot number for your hot 6mm ARC Black ammo? I have 10 boxes of 6mm ARC Black I haven't shot yet with 3 different lot numbers.
The trick is growing up without growing old. -- Casey Stengal
