6gt

Just ran a ladder on some 88gr Hammer Hunters.

Using varget, started at 32gr and went in .3 gr increments.

Ran up to a little over 3100fps before hitting pressure.

Big flat spot in velocity from 2975-3000. 32.9gr- 33.5gr all were within 25FPS and the groups were half MOA or less.

22" proof carbon barrel, 7.5 twist, everything was shot .030" jump. New Alpha OCD brass
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Just ran a ladder on some 88gr Hammer Hunters.

Using varget, started at 32gr and went in .3 gr increments.

Ran up to a little over 3100fps before hitting pressure.

Big flat spot in velocity from 2975-3000. 32.9gr- 33.5gr all were within 25FPS and the groups were half MOA or less.

22" proof carbon barrel, 7.5 twist, everything was shot .030" jump. New Alpha OCD brassView attachment 7982202

If you want more velocity try StaBall6.5. I loaded some of the 88 Hammers up in my son's 6GT, 24" barrel and it was zooming!

Deano
 
If you want more velocity try StaBall6.5. I loaded some of the 88 Hammers up in my son's 6GT, 24" barrel and it was zooming!

Deano
I haven't been a big fan of staball 6.5. It's dirty and I don't seem to get good accuracy from it in other cartridges/bullets.

I usually run H4350 in my GT with 105-112s, and figured varget would work better with a lighter bullet. Staball is actually a little slower than H4350 if I remember correctly.

I'm using unfired alpha brass and was a little surprised to get pressure so soon. It wasn't flattening primers, bit I was getting some ejector marks and slightly heavy bolt lift.

What jump did you find they like and what charge of stball? I have about 5 lbs of it laying around.
 
Who's running RL15.5 behind 110 A-Tips ??

I have some loaded to try, just haven't made it to the range yet. FWIW, 33.0 looked promising with the 109eld copy though... testing that at distance when I do the 110's too. 33.0 put me at 2819fps with a SD of 4 and ES of 10 for 10 shots in Alpha brass and BR-4 primers. 34 grains were pushing 2897fps, I forget the SD but the ES was around 18fps and seemed to be trending downward... tested 33-34 in quarter grain charges. I wanted to be in the mid to low 2800's anyway so I will not be going any higher in charge weight.
 
I have some loaded to try, just haven't made it to the range yet. FWIW, 33.0 looked promising with the 109eld copy though... testing that at distance when I do the 110's too. 33.0 put me at 2819fps with a SD of 4 and ES of 10 for 10 shots in Alpha brass and BR-4 primers. 34 grains were pushing 2897fps, I forget the SD but the ES was around 18fps and seemed to be trending downward... tested 33-34 in quarter grain charges. I wanted to be in the mid to low 2800's anyway so I will not be going any higher in charge weight.
Thanks...I just picked some up and am going to ladder both the RL 15.5 & 16
 
What’s the expected life expectancy of a barrel for the 6gt since it’s been out for a bit
I discontinued a barrel this past spring with a little more than 3400 rounds on it. Looking back my last two match scores it probably should have been taken out of service for matches around 3100.
 
I have one batch that just finished 10 firings and no issues. We anneal every firing and do not run hot. I had some go at 8 firings in another rig, but that was due to bumping shoulders a little too much.

On barrel life.....I have pulled our barrels at 2k. I did not want to risk it going into state championships. I will run them over winter to see where they actually go. But judging by scope and barrel life calculator, I think they will go between 2500 and 3k. Calculator says 2400.

We run RL 15.5 in alpha OCD. 105 to 109 grain projectiles. (We tested a bunch of stuff over pandemic bs) All loads land between 33.5 and 34.5 grains running between 2940 and 3k. We ran Bartlien and Xcaliber barrels. Various twist rates and riflings. I was running different powders too and some of the slower powders ran 36 to 37 grains. Another reason I did not want to risk it crapping out in bigger match.

On twist. We found the 7.5 twist and 5R rifling to be the easiest....cleaning, tuning, throat ware etc. The only bullet I had issues with was the Hornady 109s. They stabilized.....sometimes. They really need a 7 twist. We looked at SF #s (stability factor) and the most consistent performance was at 1.7 or higher.

On bullets......For the $ I like the Berger 108 BT. Great bullet. My favorite is the 109 LRHT but they are so scarce and expensive right, just not cost effective for as much as we shoot. 105 hybrids and 107 SMKs were good, but the heavier Bergers buck wind better.

Great cartridge and it has been fun playing with all the different stuff in these Varmint matchrs but we are looking at moving into the ELR stuff. Built a 338 Edge. 7/300 PRC and 6.5 PRC. Looking at matches that go to a mile or more. We are keeping the GTs. Just going to focus on some different stuff now.
 
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I'm wondering how close you guys are loading to the lands when getting ~3000rds of life out of a 6GT barrel..?

I've been getting ~2300rds out of my last couple 6CM barrels running them at a mildish ~2900fps and jumping a longish 0.100". I'm planning to do pretty much the same thing with my 6GT, running it "slow" (2800ish) and jumping a bunch, seems like getting 3k out of a barrel should be no problem...
 
I'm wondering how close you guys are loading to the lands when getting ~3000rds of life out of a 6GT barrel..?

I've been getting ~2300rds out of my last couple 6CM barrels running them at a mildish ~2900fps and jumping a longish 0.100". I'm planning to do pretty much the same thing with my 6GT, running it "slow" (2800ish) and jumping a bunch, seems like getting 3k out of a barrel should be no problem...
If you are running GT at 2800 is there a compelling reasons to continue to use GT over straight BR?

Are you going to run multiple/alternative loads to retain the advantages of the extra case volume? My concern with the latter approach is what happens when the throat erodes and you need to tweak/tune your load, you are stuck wasting barrel life tweaking multiple loads over the course of the barrel?

Apologies if this is off-topic, but figured maybe something people have thought about after a couple of seasons under the belt.
 
I'm wondering how close you guys are loading to the lands when getting ~3000rds of life out of a 6GT barrel..?

I've been getting ~2300rds out of my last couple 6CM barrels running them at a mildish ~2900fps and jumping a longish 0.100". I'm planning to do pretty much the same thing with my 6GT, running it "slow" (2800ish) and jumping a bunch, seems like getting 3k out of a barrel should be no problem...
I started at 60 off and never looked back.
Don't know what it's jumping now with whatever erosion there has been over 2K rounds running in the mid/high 2800's. It still prints in the 300's so I don't care what the throat/jump is. No reason to touch the seating die. I believe the target instead.
 
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If you are running GT at 2800 is there a compelling reasons to continue to use GT over straight BR?

Are you going to run multiple/alternative loads to retain the advantages of the extra case volume? My concern with the latter approach is what happens when the throat erodes and you need to tweak/tune your load, you are stuck wasting barrel life tweaking multiple loads over the course of the barrel?

Apologies if this is off-topic, but figured maybe something people have thought about after a couple of seasons under the belt.

As far as GT vs BR, IMHO, mag spacers suck, and I know like 3 guys off the top of my head that will tell you their Dashers/BR's run 100% even though I see them have a glitch or two pretty much every damn match lol. That, and you pretty much have to lean on a BR fairly hard if you spend a lot of time out at 1000+ yards (which I do).

IMHO 6GT's only real advantage over a 6CM run "slow" is that it can use Varget, which is huge, because as far as powders go, Varget is the easiest of the easy.

The only reason I'll be running "slow" is that I'd much rather have a barrel last a long time rather than push it harder and maybe only gain a tenth or so as far as better trajectory. Wind and/or wobble is usually what makes me miss most of the time, so even with a totally flat trajectory with a blaster out of Star Wars, I'd still manage to suck just fine lol. Plus, my brass lasts forever.

I don't tweak shit anymore, I just load, shoot, rinse, repeat. A huge part of the reason I'm drunk on the bullet-jump kool-aid is that with a longer jump, once you have a load that shoots, you don't have to tweak it for the life of the barrel. Super forgiving too, water-line stays stupid predictable (almost makes it seem like you got better at reloading overnight).

It's pretty simple really: with a longer jump throat erosion slows way down and the barrel becomes boringly forgiving. My first 6CM barrel's throat that I loaded 0.100" off for its whole life, only eroded ~12 thou over the course of 2300rds, guys loading 0.020" off can see that in a 200rd weekend...

It depends on what one is after: IMHO I'd rather have a gun that I don't have to mess with that only prints ~.5" at 100 (and stays 1/2 MOA out to past 1000 yards, staying boring that way for its whole long life), rather than a gun that shoots .3" groups and is dead in half the rounds.
 
8.4 SD with 190 rounds fired consecutively

37 grains H4350
108 berger
Alpha munitions 6GT brass
CCI 450
28” proof barrel 1/7T

Magneto had to be reset after 99 rounds otherwise it overrides your 99th shot with the 100th

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waiting on a 6gt barrel. It seems like everyone is mainly shooting the Berger 105 & 109 Hybrids which are pretty much impossible to find at the moment. Has anyone used the Berger 108 BT? This will strictly be a PRS round. Most matches 600-1000 yd range with an odd ball out to 1250 only shoot that once a year.
 
waiting on a 6gt barrel. It seems like everyone is mainly shooting the Berger 105 & 109 Hybrids which are pretty much impossible to find at the moment. Has anyone used the Berger 108 BT? This will strictly be a PRS round. Most matches 600-1000 yd range with an odd ball out to 1250 only shoot that once a year.
Yes, lots of stuff posted on it. Try using search function.
 
waiting on a 6gt barrel. It seems like everyone is mainly shooting the Berger 105 & 109 Hybrids which are pretty much impossible to find at the moment. Has anyone used the Berger 108 BT? This will strictly be a PRS round. Most matches 600-1000 yd range with an odd ball out to 1250 only shoot that once a year.
A friend uses it for prs... told me it was super consistent and grouped well on target but gets a little loose when the wind kicks up.
 
A friend uses it for prs... told me it was super consistent and grouped well on target but gets a little loose in when the wind kicks up.
I have been running the 108gr ELDM's @2930fps with hornady brass and H4350. It is easy to tune and does well enough in the wind. I have shot my 6GT out to a mile with good results. It holds its own.
I wish I could find Bergers locally. If I could I would shoot them over theELDM'S.
 
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I have been running the 108gr ELDM's @2930fps with hornady brass and H4350. It is easy to tune and does well enough in the wind. I have shot my 6GT out to a mile with good results. It holds its own.
I wish I could find Bergers locally. If I could I would shoot them over theELDM'S.
I was happy with the 108 ELD as well when I ran it earlier this year. Applied Ballistics gave it one of the most consistent BC SD's too.
 
Considering switching to 6 Dasher when my GT barrel goes. Is there any reason to do that or am I just overthinking this? I really don't know why I'm considering Dasher but, is there any reason to consider it? I'm only shooting PRS type matches if that matters.
 
Considering switching to 6 Dasher when my GT barrel goes. Is there any reason to do that or am I just overthinking this? I really don't know why I'm considering Dasher but, is there any reason to consider it? I'm only shooting PRS type matches if that matters.
Absolutely no reason if you already have dies, components, etc. Just another expensive workup.
 
Impact 737 proof pre fit 26"(altus) powder: 6.5 staball. Brass: alpha ocd primer: cci450. Bullet: 108 eldm. Charge weight: 38.0. Velocity: 2875 This is a load I been shooting for about a year or so in two different Gt barrels. I shot 5 matches this year with this load and it shoots as good as anything I have loaded, including varget, h4350, and swp. It usually hovers around 8-10 sd, with es around 20, on 25 shot strings. All charges dropped from Hornady powder thrower, with Hornady dies. No scales, no trickling. Holds waterlines out to 1000 yards with ease. Powder is dirty, but haven't had any problems with accuracy or carbon rings during two day matches. I'm not saying it's the best powder, but it will make you rethink sitting there for hours weighing and trickling.
 
Considering switching to 6 Dasher when my GT barrel goes. Is there any reason to do that or am I just overthinking this? I really don't know why I'm considering Dasher but, is there any reason to consider it? I'm only shooting PRS type matches if that matters.
Why? What does the Dasher do for you that the GT isn't? (not rhetorical, not being a smart ass, genuinely curious on your reasoning or thought process)