Could possibly be dirty guess i’ll clean this thing.
And ammo was in my pack not in direct sunlight.
6gt
- Thread starter Dthomas3523
- Start date
And ammo was in my pack not in direct sunlight.
Shot this GAP PPR again today. 34.5 grains of h4350 and 107 smk. 10 to 15 mph sustained with 25 gusts.
Re-mounted scope, 2 into 200 yard back stop, then 3 shot group on paper.
Rifle and round is rocking...
Even with some wind fliers it's good, or perhaps me flyers...
Re-mounted scope, 2 into 200 yard back stop, then 3 shot group on paper.
Rifle and round is rocking...
Even with some wind fliers it's good, or perhaps me flyers...
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I run nearly an identical load except I use CCI 450s and get about 30 fps faster. No heavy bolt lift and it shoots extremely well. As long as my ballistic app is set up properly.*
*Was shooting a match today but everything beyond 500 yards was falling way short. Turns out I did "something" to my Strelok Pro app and was getting about 1-1.5 MILS short of actual dope. i.e Strelok was telling me 7.7 mils for 1141 when I needed 9.2. Only figured out the issue when I compared notes from the same match in June. But that's another subject altogether. I'm just happy I it was the app and not the tracking on my scope.
Man I run 36.2gr h4350 with same bullet from a 28" barrel at 2910-2920 cci450. Its an extremely mild load, i can get near 3080fps before bolt lift on an ARC nucleus gen2. How many firings? Check the diameter of a sized case at the web area vs a fired. Perhaps the web isn't getting sized enough by your dies? 3k bump is a bit more than necessary, I usually strip my bolt down and size a case just enough to get the the bolt handle to falls shut on its own weight, and go one more thou, usually works out to 0015 or 002 from fired.
This would be #2 for me. If carbon is not an issue it is most likely this. Great post.
Thanks man! Another thing...... @Turbwhistle do you know the barrels bore diameter? My first 6gt was a 236 bore diameter Krieger. It shot lights out with 108bt bergers at 2950 till about 800 rounds. Then it went way wonky psi all over the place. The 236 vs 237 bore will bring up psi by quite a bit fouling only makes it worse. I cleaned the living hell out of that thing, abrasives, bronze brush on a drill to clean any and all copper/carbon from neck and leade. It was spotless yet never could get back to the prior speed without ejector and bolt lift, my belief ot developed enough roughness and fire cracking it waa just grabbing the bullet more at this point and it was there to stay. My primers were flat though, obvious over psi signs, but Horandy brass was being used on that barrel. Lesson learned, dont get a tight bore barrel in 22 or 6mm caliber blanks. It'll only cause problems.
#3. Not knowing round count. Why I asked about carbon first. But I am on barrel #4 and the first one I had was tight. Same thing around 600. Tried everything. Was toast around 850. Barrel smith cut it open, said it looked like 3k plus. I was running 32 something of N150. I have moved on to RL15.5. Over 1k on these 2. Should get 2400ish to 3k on them, so says the barrel life calculator. It is funny how the GT seems to be a bit more finicky with carbon and pressure.
Agreed, they're a bit more temperamental than a br variant, however still better than a 6cm for staying in tune. My 28" 7.5tw mod400 bartlein has 1900 rounds on it. The throat has moved near 60k since new. Original load development was 40k jump with 109s, its now jumping around 100k, I have not adjusted as it still shoots half moa or better on paper at 500y. I have added 0.2gr powder to keep the velocity at 2920 or so with the throat erosion. I really expected the harder bartlein alloy to hold in longer than that, but fire cracking isn't too bad, I think it'll go 3k rounds. I should probably retune the load, however I now have about 210 freebore as it was cut 150 to start. Might just switch to dtacs since I have plenty of room for them now.
I'm through my first lot of 500 GAP Hornady brass, are these codes still valid for Anealing Made Perfect:
"Aztec mode use 142 for Hornady, 141 for Alpha"
Going to anneal this lot of brass for the first time, I'd rather not waste a case if these numbers are valid.
Also, loading up SMK 107's with H4350, my first loading was 34.5 grains, getting on average a bit over 2700 fps and good accuracy. What grains have shown good results and no over pressure signs with this combo?
Thanks
"Aztec mode use 142 for Hornady, 141 for Alpha"
Going to anneal this lot of brass for the first time, I'd rather not waste a case if these numbers are valid.
Also, loading up SMK 107's with H4350, my first loading was 34.5 grains, getting on average a bit over 2700 fps and good accuracy. What grains have shown good results and no over pressure signs with this combo?
Thanks
140,141,142 wont make much a difference. You're worried about losing a case? Don't go shoot any matches, you'll lose at least a few every time.
They are linear numbers so I'd be surprised if one guy can outshoot a 142 over a 145 annealing.
My GT won’t be ready for another few weeks but have gathered up powder/bullets/ dies all I need is brass. Is there a general consensus on wether OCD is .50 cents apiece better than Hornady?
Hornady 109 factory ammo is getting me top 10 finishes and production wins. I love not having to deal with sitting at the reloading bench. The amount of time saved is incredible. I don’t even need to pick up my brass anymore on stages.
I know this is a reloading thread but I thought it may be valuable to anyone who is on the fence and feels like they need to reload.
This stuff rocks.
9.3 SD were the first 5 rounds out of the rifle.
The other image was round 175-179 after the final PRS stage for the day.
I know this is a reloading thread but I thought it may be valuable to anyone who is on the fence and feels like they need to reload.
This stuff rocks.
9.3 SD were the first 5 rounds out of the rifle.
The other image was round 175-179 after the final PRS stage for the day.
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Alpha vs Hdy: Depends on how you define "better". My GT shoots under 1/2 MOA all day long with new Hornady brass. I run 34.4 gr of Varget behind 109 LRHTs and the cases handle the pressure just fine - even on really hot days. For me, the only way Alpha brass would be 50% better is it gave me 50% more loadings. I'm a ways off from finding out how many I can get out of the Hornady brass.
Anyone use a 6CM seating die with 6GT..?
I’m getting my shit together for my next barrel (going from 6CM to 6GT, for no other reason than I’m switching to SRP’s from LRP’s, so why not) and can’t really think of any reason why a 6CM die wouldn’t be fine?
FWIW, it’s a Forster Ultra Micrometer Seater…
I’m getting my shit together for my next barrel (going from 6CM to 6GT, for no other reason than I’m switching to SRP’s from LRP’s, so why not) and can’t really think of any reason why a 6CM die wouldn’t be fine?
FWIW, it’s a Forster Ultra Micrometer Seater…
I know, but since I was buying hundreds of dollars of new brass, figured I’d make the switch…
GAP/Alpha’s “Gay Tiger” headstamp pushed me over the edge lol
Don’t know about the Forester? It might not adjust short enough.
FWIW - I’m using the SAC seating die for 308, 6.5C, 25C, 6GT, 6.8SPC, 224V, & 6ARC. I made a couple step down sleeves for SPC & Grendel sized cases. Works great.
I compared the SAC seater to my Widdon seater for the 6GT and saw no discernible difference in run out.
FWIW/FYI, I emailed Forster about using their 6CM Ultra Mic seating die for 6GT and their Technical Support got back to me...
Holy shit! An actual thoughtful response! Good on them, and good to know they don't just "mail it in" like so many companies do:
"Our seating die chamber is oversized by .004-.005", so you shouldn't have an issue with the diameters. The seating die chamber is designed to have the case supported on the shoulder within the die. This means that the 6GT case would not touch the shoulder portion of the 6CM die chamber due to the body length difference which can potentially throw run out in your operation. This could be remedied by shortening the die chamber by ~.180".
All that said, yes, you could certainly make this work. I do also want to let you know we're adding the 6GT sizing and seating dies to our lineup. You could expect these to become available in the next month or two.
Regards,"
I have already ordered the custom Hornady set from GAP because I actually like the idea of a custom-honed .266 FL die (not to mention I like having a back-up set of dies for "just in case" anyway), but I'll probably snag one of the Forster's when they're available, I really like their seater.
I'll gut the FL die of any expander nonsense and will follow it with a .241 mandrel. If the Hornady doesn't work out, I'll pick up a Wilson bushing die (which is what I've been using in 6CM for my last 3 barrels).
Holy shit! An actual thoughtful response! Good on them, and good to know they don't just "mail it in" like so many companies do:
"Our seating die chamber is oversized by .004-.005", so you shouldn't have an issue with the diameters. The seating die chamber is designed to have the case supported on the shoulder within the die. This means that the 6GT case would not touch the shoulder portion of the 6CM die chamber due to the body length difference which can potentially throw run out in your operation. This could be remedied by shortening the die chamber by ~.180".
All that said, yes, you could certainly make this work. I do also want to let you know we're adding the 6GT sizing and seating dies to our lineup. You could expect these to become available in the next month or two.
Regards,"
I have already ordered the custom Hornady set from GAP because I actually like the idea of a custom-honed .266 FL die (not to mention I like having a back-up set of dies for "just in case" anyway), but I'll probably snag one of the Forster's when they're available, I really like their seater.
I'll gut the FL die of any expander nonsense and will follow it with a .241 mandrel. If the Hornady doesn't work out, I'll pick up a Wilson bushing die (which is what I've been using in 6CM for my last 3 barrels).
What are you paying per round for factory loaded and where are you getting it?
nearly a carbon copy of mine when I started.
33.6 to 33.8 is a pretty common area to settle into.
I’ve been running, a GAP 26” barrel chambered in 6GT, groups at .28< with 37.6 gr staball 6.5, just under 55psi, .002” seat at 1.970 depth bto with Berger 105vlds. Been consistent at avg mv right around 2855. Fed match mar205 primers, alpha brass.
One my second barrel now from GAP, I’ve learned to stay under the 2900fps for a consistent flat waterline.
One my second barrel now from GAP, I’ve learned to stay under the 2900fps for a consistent flat waterline.
I got 15 firings from the Hornady brass before slight case head separations occurred on 7 out of 100.
My first load with 109’s was 33.8. Switched to a new lot of Varget and warmer temps and mine started doing the same. Velocity was 2952 fps. I dropped down to the lower node of 32.6. Velocity is only 2850 now but it shoots really well and don’t have to worry about over pressure anymore.
I’m no mathmatologist so could someone explain what it means when the line thingy goes more sideways than up in one of these? There’s been a few now. Not gonna lie I didn’t know how to do it until I saw the unknown munitions one a couple posts before.
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It means nothing. It's a Rorschach test... guys see what they want to see.
Some may call it a "node" they found using their "data"... but they'd be willfully ignoring the overwhelming likelihood that the anomaly they observed was just a simple coincidence, especially since it occurred while shooting a painfully small sample size of rounds (nowhere near enough to know anything or say anything with any certainty). Some of those same guys also speak of performing tedious and ridiculous rituals as essential to breaking in a new barrel. Some even claim to have possessed lots of bullets that went to sleep on them at inopportune times. Sleeping bullets.
If you want to burn 50rds worth of components and barrel life figuring out that, with that powder in that barrel, ~33 grains nets ~2850fps, and ~34gr nets ~2950... that's cool. Just know, you could've figured that out with 2 rounds, and then loaded 48 at your preferred speed.
Combustion requires fuel (powder), more fuel means more combustion, so more powder means more speed, derp. Combustion remaining constant while adding more fuel is not a thing (ask NASA).
If you ever run into an actual person educated and practiced in combustion and propulsion at a party, see how far you can get into explaining "nodes" and/or an "OCW test" before they spit out their drink laughing...
I like that there are still some guys involved with this shit who are having fun and don't take this shit too seriously.
George to the rescue!
Speaking of 6GT, I'm just about ready to prime and charge 500 cases...
H4350 and Hornady brass, was @ 34.5 grains and typical velocity of 2700. Maybe I'll bump it up to 35.5 - 36 grains. Thoughts?
Speaking of 6GT, I'm just about ready to prime and charge 500 cases...
H4350 and Hornady brass, was @ 34.5 grains and typical velocity of 2700. Maybe I'll bump it up to 35.5 - 36 grains. Thoughts?
~2860fps has worked great for me on the last 4 barrels with H4250 and 109s.
I have no first-hand experience with 6GT just yet, but IMO, with any cartridge, that's pretty much the only reason to bother doing a ladder... to find out what it takes to get the speed you want and/or what you can have while remaining safely under the "oh shit" zone. Since I'm not as obsessed with speed as some, I don't usually load hot enough to where I'd have to worry about pressure. YMMV.
I'm curious where I want to end up speed-wise with 6GT myself..?
I've been running "only" 2900fps with 6CM for a long time now and combined with using a jump bigger than most (0.100" off), I got 2300rds out of my 1st 6CM Proof prefit barrel, and am about ~400rds into #2 of the same thing using the exact same load... I would like to get around 2300 or so out of the 6GT barrel too, more if I can... I'm just not sure which range will be best for its usable life: 2700, 2800, 2900fps... IDK?
I've got my barrel (Proof SS prefit), got my primers (CCI450's) and have got my brass (Alpha Gay Tiger), but I'm still on the fence about what powder and bullet to roll with.
I had 16lbs of RL16 in my cart this morning that was gone before I found my CC, but honestly, I'm not sure what I want to sign up for. I buy all my components for a barrel up front in bulk, enough to shoot it out, so I need to pick a bullet and find 2500 of 'em, and pick a powder and find 16lbs of it.
Life has been pretty easy using Sta-Ball in 6CM and it's worked great for me, so I may just stick with that, but since Varget is starting to become attainable again I was leaning that way, that or H4350/RL16, IDK...
I'm on the fence between DTAC 115's, 112 Match Burners and/or the 109ELD-M's too... decisions, decisions...
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I have 6.5 Stabal, Varget, & H4350 on hand, but I started the 6GT on Vit N555. Never had to hunt for a load in this thing. Works so well I've had no reason to try anything else.
38.6 of N555 with Berger 109's = 2920 from a 26" PVA. Nice case fill & is a pretty clean burning temp stable powder in my experience so far.
There was no hint of pressure signs at that speed. I just stopped there because it was a full case & saw no point in chasing speed any higher.
2800 - 2930 with Berger 105 hybrid or 109 LRHT it shoots the same tiny groups. Like you said pick your speed.
38.6 of N555 with Berger 109's = 2920 from a 26" PVA. Nice case fill & is a pretty clean burning temp stable powder in my experience so far.
There was no hint of pressure signs at that speed. I just stopped there because it was a full case & saw no point in chasing speed any higher.
2800 - 2930 with Berger 105 hybrid or 109 LRHT it shoots the same tiny groups. Like you said pick your speed.
I decided I'll see what happens with SW Precision Rifle + 112gr Match Burners in the 6GT...
I probably overpaid for the Shooter's World stuff, but finding it in-stock at Midsouth and not having to be on the seemingly endless treasure hunt for Varget does have a certain worth IMO lol. According to the John Snow article a while back, the cartridge was loosely designed around playing nice with Varget and that type of faster burn rate, so I'm curious about all that. This will be new to me since the fastest stuff I'm familiar with is H4350/RL16/Staball, but seems like loading for anything that takes Varget is a piece of cake from what guys yap about...
I went with the 112MB's simply because I've shot a boatload of them at this point and they've been great, not to mention getting a ~.305 G7 for ~$0.27 a pull. I originally bought a bunch because that's all I could find and the numbers looked like a good substitute for DTAC's (when they became unavailable/unattainable), and they've been a legit stand-in for those. I'm not going to say they're as good as Berger 109HT's or A-tips, but they're a hell of a lot better than most guys think, certainly not half as good while costing half as much. (FWIW I jump the hell out of them, 0.100" off is my go-to, I've never shot them any closer than 0.060" off.)
I'm planning to save the 6GT barrel until my current 6CM barrel is shot out, but depending on how things go this winter, who knows... Staball has been no problem for me in temps above 60degF, but in the colder months, I've had a couple of days/matches where my dope was fucked up until the temps warmed up and/or I figured it out so IDK.
I probably overpaid for the Shooter's World stuff, but finding it in-stock at Midsouth and not having to be on the seemingly endless treasure hunt for Varget does have a certain worth IMO lol. According to the John Snow article a while back, the cartridge was loosely designed around playing nice with Varget and that type of faster burn rate, so I'm curious about all that. This will be new to me since the fastest stuff I'm familiar with is H4350/RL16/Staball, but seems like loading for anything that takes Varget is a piece of cake from what guys yap about...
I went with the 112MB's simply because I've shot a boatload of them at this point and they've been great, not to mention getting a ~.305 G7 for ~$0.27 a pull. I originally bought a bunch because that's all I could find and the numbers looked like a good substitute for DTAC's (when they became unavailable/unattainable), and they've been a legit stand-in for those. I'm not going to say they're as good as Berger 109HT's or A-tips, but they're a hell of a lot better than most guys think, certainly not half as good while costing half as much. (FWIW I jump the hell out of them, 0.100" off is my go-to, I've never shot them any closer than 0.060" off.)
I'm planning to save the 6GT barrel until my current 6CM barrel is shot out, but depending on how things go this winter, who knows... Staball has been no problem for me in temps above 60degF, but in the colder months, I've had a couple of days/matches where my dope was fucked up until the temps warmed up and/or I figured it out so IDK.
I hope you have good results. That combo was stupid accurate and consistent for me. But slow
