If you're getting case head separation it's a reloading issue not the brass..
Get the headspace gauge out and stop pushing the shoulder back beyond .002
6gt
- Thread starter Dthomas3523
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Get the headspace gauge out and stop pushing the shoulder back beyond .002
Seat bullet to neck shoulder junction. Check to see if it fits magazine. Check to see if it feeds. Go shoot.
Hornady is known for shitty 6GT brass, it's been documented since 2019ish... One of my shooting partners had case head separation on day 2 of a team match, on reload #2. 2850 with 105 hybrids, so very mild load.
No you get the proper gauges hornady makes them comparator sets and then you adjust based off that most people start 10k off the lands just depends on many variables. Might want to look in the reloading section they have specific threads and step by step guidance
Without measuring headspace anecdotal stories are useless, I'm not defending Hornady by any means but I've had the same thing happen with Peterson and Lapua brass.
One instance was my fault bumping the shoulder too much, the other either excessive headspace of .010 or brass out of spec.
Now I always measure case growth on the first firing, you'd be surprised how often virgin cases are short of proper headspace.
Stretch them once you might be ok, twice and you're done.
You asked in this post: https://www.snipershide.com/shooting/threads/6gt.7053224/post-11523601
About brass options, a few of us chimed in... Hornady brass in 6GT is WELL DOCUMENTED to suck balls. So, anecdotal stories are what you're gonna get. YMMV.
This particular person is a known gunsmith and ammo FFL (and a member here)... So, I'm pretty damn sure he knows what he is doing.
Like I said, I have multiple seasons and tens of thousands of rounds with 6GT, so take that as a clueless opinion. I ran my first season in 6GT with Hornady brass. I learned my lesson the hard way, I'm simply promoting that people don't make the same expensive mistake.
Good luck
Only pushed back .002 every time. Annealed every time. SAC dies and SAC comparator.
One rifle I was running hornady brass and one alpha. Hornady brass gave out alpha didn’t. Using sac sizing die for each(not using the same die for both). Hornady gave out. Alpha is still going strong. Basically same loads in both rifles. I did push the alpha brass more with some higher speeds. But only a few times.
NiteQwill,
What does it mean to seat bullet to neck shoulder junction? It sounds like you are saying to line up the bottom of the bullet with the area where the shoulder becomes the neck? Is so, how do you do that?
I do understand what this means, although I am going to need to watch some Youtube videos of folks doing it and read more here using the search function about which tools to get. I bought the Hornady Lock N Load OAL gauge and the modified case (in 6mm GT) that GA Precision sells. That case is Hornady, but I am loading Alpha. I have not yet bought any comparator sets because I still need to figure out which ones I need to get and how to use them, but that is the very next item on my road to starting reloading (finally, whew! it's a lot to learn).
I suggest reading this article to understand a bit: https://precisionrifleblog.com/2020/04/28/bullet-jump-research-and-load-development-tips/
If you want consistent CBTO measurement that can repeatable, I suggest skipping the Hornady comparators, and look into SAC or Area419 instead. Use a good set of Mito calipers.
So everyone using Hornady measuring tools doesn’t have a repeatable CBTO measurement ?
Interesting…..
You can quickly figure out a rough idea if your bullet is seated with the bearing surface even with the neck shoulder junction by looking at a loaded cartridge with a bare projectile next to it. I'm attaching a quickly found image *that would be better if the same bullet were used*...but hopefully you get the idea. Some bullets will protrude more or less depending on jump, bullet length, and chamber dimensions.
There are a lot of discussions that revolve around this relationship. I am not trying to enter any...just trying to help you understand what he is talking about.
Also, when you use that Hornady OAL comparator gauge with the special cases it will not make a difference whether your case is Hornady or Alpha. It is taking a measurement from the bottom of the case to the point in the bullet's ogive where it makes contact with the lands in your barrel. Please also understand that you are going to be measuring jam and not touch. I bet you'll find out that you leave your bullet stuck in the barrel more than not with the Hornady gauge.
Correct, so if I used my Hornady comparators and got measurements off said bullet and gave you MY measurements, it wouldn't be the same that you get. The SAC and Area419 allows it to be repeatable from shooter to shooter. That is the selling point of the latter.
The Hornady gets you there, it's just sloppier.
So if my shooting buddy and I are shooting a team match, we live in different states, and want the same load and length to our rounds... All we do is send numbers to each other. We arrive at said match and have exactly the same ammo.
I have noticed a few thousandths variation when I use my Hornady comparator...which is why I do three measurements and take the median one. I also never start load development at jam, so I have a little wiggle room just in case.
I would venture to guess that how hard you push on the rod would have a little say in the overall measurement you get.
If you have 500 virgin cases (especially Alpha), I'd just mandrel the case neck (or run over an expander ball), chamfer, and load.
Actually, 500 Alpha cases are probably going to outlast your barrel by quite a bit.
They are Alpha, and Brownells is shipping me a .241" TiN coated mandrel and expander die as we type, but I still need to select some sort of seating depth for the bullet, which is what sparked my question last night, above, in post # 1,849.
I got that. I quoted and responded to your question in #1,867.
If you've never fired a round down the tube, load a couple rounds to whatever spec you are getting your load data from (Hodgdon, Hornady etc...). Use those rounds to confirm zero and start whatever break-in you do or don't believe in.
I now determine my OAL by putting a small amount of blue loctite around the bottom of a bullet's bearing surface and load it LONG in a freshly fired case (not resized, but deprimed), wiping off any excess. I then carefully chamber it - closing the bolt fully - and let it be for at least a half hour. You've effectively pushed that bullet forward into the lands and have found one way (there are multiple) of figuring out where jam is in your chamber. When you open the bolt, the bullet is glued inside the case. It doesn't take gorilla strength to separate, and you can just run a case mouth brush in the neck and scrub off the dried loctite.
I stopped using the Hornady OAL finding gauge because I WAS getting inconsistent readings by a few thousandths.
There are videos showing the method I described. If you can remove your barrel easily, there are other ways.
Thanks.
I have put a 120-130 rounds down the tube, almost all Hornady Match commercial ammunition, along with some reloads of 110 grain A-tips that were intended for Robert Brantley's rifle. The Hornady commercial ammunition experienced the dreaded primer piercing due to my .068" firing pin. The reloads using 205M primers did not.
So now I have been buying up what I need to reload (dies, brass, bullets, powder, primers, RCBS chargemaster link, and more) starting from scratch with no experience.
I have put a 120-130 rounds down the tube, almost all Hornady Match commercial ammunition, along with some reloads of 110 grain A-tips that were intended for Robert Brantley's rifle. The Hornady commercial ammunition experienced the dreaded primer piercing due to my .068" firing pin. The reloads using 205M primers did not.
So now I have been buying up what I need to reload (dies, brass, bullets, powder, primers, RCBS chargemaster link, and more) starting from scratch with no experience.
It's a fun ride. Bonus that you picked the 6GT to learn on. It is one of the most forgiving cartridges I've found. Three bullets, three powders, and I don't think I've fired a single five shot group that has exceeded MOA.
Best of luck.
Well shitYou asked in this post: https://www.snipershide.com/shooting/threads/6gt.7053224/post-11523601
About brass options, a few of us chimed in... Hornady brass in 6GT is WELL DOCUMENTED to suck balls. So, anecdotal stories are what you're gonna get. YMMV.
This particular person is a known gunsmith and ammo FFL (and a member here)... So, I'm pretty damn sure he knows what he is doing.
Like I said, I have multiple seasons and tens of thousands of rounds with 6GT, so take that as a clueless opinion. I ran my first season in 6GT with Hornady brass. I learned my lesson the hard way, I'm simply promoting that people don't make the same expensive mistake.
Good luck
Now I have to buy some Hornady brass just to see if I get case head separation in two firings..
I'll put up honest results when I get the barrel
I can answer that …my Hornady brass is on its 5th firing no case separation primer pockets are good. Feel pretty confident I can get a couple more firings so was worth the money. I have a few hundred Alpha but haven’t loaded them yet.
Did you need to do any tuning? I have just 2 of these. They would not feed 6.5 at all. Seemed quite altered with 6gt with the case base dipping easily, however they would seem to feed fine. Still trying to diagnose the issue.
I just got a couple of these new 12rnd amend2 poly mags to try. Cycled 12 rounds through both my 25x47 and 6gt and they worked great, no hiccups. They are slightly longer than a mdt 12rnd by .33" but shorter than a AICS 10rnd with a +2 extension on it. Max coal is at or real close to 2.9"
Anyone have the Berger page for the 105 Load data? Please 
and thank you
and thank you 
I have with 107 SMK’s, I’m actually looking for a place to start with 105 Berger’s I just got.
Use the same start data as the 107s. All the QL data I’ve gotten from Berger has been very conservative.
I am building a 6mmGT as a light, 18 inch barrelled rifle.
In my chosen contour/make of barrel, I can get a 1:8" twist easily and may have to wait a long time for a 1:7.5". I would prefer a 1:7.5" twist, but I am non-USA so parts availability is an issue.
I want to shoot the 108gr ELDM (actually 109gr ELDM but as I'm non-USA and they seem to be GAP exclusive, I'm shit out of luck - @A10XRIFLE hook us internationals up)
If the 108 ELDM doesn't shoot in my barrel, it looks like a 105, 108, 109 Berger, 103 ELDX, etc will work as backup options with stability in a 1:8. I want good terminal performance hence my preference for the ELDM (I use these in .22 and 6.5mm with excellent effect)
I expect to get up to something in the range of 2750-2850FPS using Varget/H4350 and Alpha or Lapua brass (if it becomes available).
Has anyone got experience with a 1:8" 6mmGT and the 108gr ELDM, or any of these other bullets? Have you experienced stability issues?
In my chosen contour/make of barrel, I can get a 1:8" twist easily and may have to wait a long time for a 1:7.5". I would prefer a 1:7.5" twist, but I am non-USA so parts availability is an issue.
I want to shoot the 108gr ELDM (actually 109gr ELDM but as I'm non-USA and they seem to be GAP exclusive, I'm shit out of luck - @A10XRIFLE hook us internationals up)
If the 108 ELDM doesn't shoot in my barrel, it looks like a 105, 108, 109 Berger, 103 ELDX, etc will work as backup options with stability in a 1:8. I want good terminal performance hence my preference for the ELDM (I use these in .22 and 6.5mm with excellent effect)
I expect to get up to something in the range of 2750-2850FPS using Varget/H4350 and Alpha or Lapua brass (if it becomes available).
Has anyone got experience with a 1:8" 6mmGT and the 108gr ELDM, or any of these other bullets? Have you experienced stability issues?
VV N150 will work for sure. Just tried it today for the first time...no issues.
I think I've seen RL16 being used here, but that stuff is rare and expensive! VV N555 might work if not too bulky or slow burning.
105 Hybrid at 1.947 CBTO
1x fired Alpha
Fed 205MAR
N150 and H4350
Cleaned my 27" Krieger back to bare metal after 200 rounds and started a little more load development today.
Took a stab in the dark with N150, and also shot a few groups with the same charge weight range of H4350 that my barrel prefers the 108gr ELD-M with.
Both times I ran out the top end for accuracy, and the groups opened up on the last charge.
*Just 5 shots per.
N150 after a single fouling shot:
Then I tried H4350. Lowest was best, with the next throwing a shot out, and the final highest charge spitting out two shots (still was a .5).
Looks like I have just a little verifying to do and then I'm good.
ES and SD were everything I could hope for. I know...small sample sizes, but with that many I think there is some consistency there.
1x fired Alpha
Fed 205MAR
N150 and H4350
Cleaned my 27" Krieger back to bare metal after 200 rounds and started a little more load development today.
Took a stab in the dark with N150, and also shot a few groups with the same charge weight range of H4350 that my barrel prefers the 108gr ELD-M with.
Both times I ran out the top end for accuracy, and the groups opened up on the last charge.
*Just 5 shots per.
N150 after a single fouling shot:
Then I tried H4350. Lowest was best, with the next throwing a shot out, and the final highest charge spitting out two shots (still was a .5).
Looks like I have just a little verifying to do and then I'm good.
ES and SD were everything I could hope for. I know...small sample sizes, but with that many I think there is some consistency there.
I want to try that one and I heard N140 is good.
Yes, I know others who tried RL16 and had good results but like you said, rare and expensive, just like H4350
I tried 33.2, 33.5, 33.8 N150 in post #1,887 above.
Surprisingly my ES and SD went up with each charge weight.
I'm going to add a screenshot of the post where I saw the only load data for N150 so far:
I had my 26” criterion cut down to 20” and only lost 80fps wjth the same load. Thats 13.3 fps per inch.
I’m at 34.2 varget 112 match burners.
I took 10 rounds to the range to test, 1 to make sure I was on paper (new scope)
9 shot group, here’s the data.
I’m at 34.2 varget 112 match burners.
I took 10 rounds to the range to test, 1 to make sure I was on paper (new scope)
9 shot group, here’s the data.
Has anyone tried N140? Just got my barrel and I'm about done paying ludicrous H4350/Varget prices
Just curious why you shortened the barrel? Scientific curiosity? Easier to handle indoors? Shorter overall length when using a silencer? Easier to use on the five rungs that F@#king lightweight aluminum stepladder the match director set up for one of the stages?
I hate long barrels. Always have. Even more since I started shooting with a can years ago. I saw someone on the 6gt FB page that had the same load as me and cut theirs to 20” and had good velocity, so I went for it.
I wish I would have cut it to 18” and upped the charge .2gr or so to keep it at 2800.
Did a depth test this morning.
This was the last 5, mirage was trying to mess with me but I’m happy with this load and rifle.
This was the last 5, mirage was trying to mess with me but I’m happy with this load and rifle.
I don't think N160 will be optimal for sure, but you could probably get it to work if you had to. I just looked at some burn rate charts, and it is a lot closer to H4381 than it is H4350.
IMO N160 is going to be better once you get up to 6CM. N150 however is right up there with powders I've had good luck with.
Here is another 6GT load data point:
Sierra 107 SMK
34.0 grains Varget
BR4 Primer
18 rounds fired
21.5" barrel - 1/7.5 twist
Min 2905
Avg 2915
Max 2935
ES 29.5
SD 7.2
Dialed 2.9 Mils at 600 yards
Sierra 107 SMK
34.0 grains Varget
BR4 Primer
18 rounds fired
21.5" barrel - 1/7.5 twist
Min 2905
Avg 2915
Max 2935
ES 29.5
SD 7.2
Dialed 2.9 Mils at 600 yards
Very well. We were shooting at 600 and I did not measure group size. My previous 5 shot group size with the same load at 100 was .325 MOA.
I'm 30 rounds deep in my proof competition contour 6GT barrel, so far N150 and H4350 are shooting great around 2850 with Dtacs.
Just for fun I loaded 112 match burners up today with 39 grains N160, 6 shots total averaged 2825 with an SD of 12.
The 1" group is .025 off the lands, the other .050 off.
Just for fun I loaded 112 match burners up today with 39 grains N160, 6 shots total averaged 2825 with an SD of 12.
The 1" group is .025 off the lands, the other .050 off.
