6gt
- Thread starter Dthomas3523
- Start date
I second what @LR1845 said, 600y benchrest/f class is dominated by 6br variants. I really like the 6bra with lapua brass.
With 33 grains you should be close to that, I’m at 34 grains of varget with Berger 108’s out of a 26” barrel with mv of 2920
Thought I was taking it easy with 105 Hybrids and 33.5 grains of Varget out of a 26 inch barrel. 2904 fps.
Ya, I third what 406 and LR1845 are saying. I am currently running a 6GT and it has been great, learned a lot with it, I have shot some really good groups with it. However I am currently in the process of building a Dasher. They are just better suited for going down the road you are on.
But back to your original question between 6GT and 6 creed, my vote is 6GT, has been easy to load, components are becoming more and more available everyday. 32.6 of varget and a 105 Berg Hyb was an easy button for me in the low category of 2850ish.
The 32-33gn range is probably it for 2800-2850fps (depending on whether you've got a faster or slower barrel). I've run a shitload of Shooters World Precision Rifle (basically slightly slower Varget) in the GT, and 32gn nets me ~2760fps, 33gn nets me 2805fps with a 106 A-Tip.
FWIW and sort of related, I no longer believe case-fill is as big of a deal as some make it out to be in order to get low SDs, but I do sort of believe there is something magical about using the faster burning Varget-like powders (SWPR, N140, N150, etc).
Ever since I got an Ingenuity Precision trickler and all my ammo has been loaded with charges always within +/- a single kernel of each other, when using SWPR or Varget, everything shoots, and I haven't seen an SD over 20 shots that wasn't in the single digits in ~2+ years now.
I even started experimenting with my 6CM barrels and have been running a load that hammers that just about any old fudd would tell you is completely wrong: a heavier 112gn MB with only 36gn of SWPR in 6CM, the cases are maybe 3/4 full and sound like salt and pepper shakers when I shake them... straight-up hammers, and my SDs average ~7 over 20 shots.
I’m in the boat also. I shoot my 6.5cm at 40.5g of h4350 ant 2700 ish and seat them long with a COAL of 2.90. Hammers and I sounds like a salt shaker also with sd’s in the 6-8 range always.
When I get my gt up and running I’ll do the same with that catridge. 2750-2800
Depending on the characteristics of the barrel I've run 31.5 - 32.5 which has put me in the 2830 range from 26" barrels using 108 and 109 bergers and 110 A-tips.
Was shooting H4350 at 37.6g with 108 Bergers. Wanting to try some Varget so ended up settling on 34.5g with the 108’s. Varget showed me better consistency on target and over the Garmin.
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H4350 and some of the others in that burn range are no slouches... but I'm drinking the Kool-Aid on using the faster Varget-alike powders in the 6GT. Less powder means less recoil (easier to spot splash/impacts) and the faster powders just make things easy.
This is 33gn Shooters World Precision Rifle under a 106gn A-Tip, average 100 group is ~.3" (hammers out to 1250 yards too):
This is 33gn Shooters World Precision Rifle under a 106gn A-Tip, average 100 group is ~.3" (hammers out to 1250 yards too):
I have not. The MDT AICS 10rd metal mags work great for me.
Just to be clear, I have MDT metal mags in 10 and 12 rd , ai and accurate 10rd mags. Just wondering if anyone has tried the 6gt poly mags. I ordered a couple while they were on sale.
I have had great luck with Amend2 12 rnd mags with the 6gt. It's nice to be able to pick them up for under 20 bucks too.
Not sure if I have used any mdt poly's
Not sure if I have used any mdt poly's
Just got a poly MDT mag a while ago, works slick. Using it in a MDT XRS chassis on a Tikka build.
If anyone is shooting alpha 6gt and 109 hybrids and has the Area 419 comparator set. What’s your CBTO? I’m removing my ejector and the bolt drops free at 1.911 with a light click at the top. I’m subtracting .025 to be 025 off the lands. Curious what others are getting with this setup.
I start at .055 to .060 off touch with 109's in Alpha. Load depends on barrel but usually I'm around 31.5 to 32.5 of varget in a 26" barrel and load to 2830 to 2850. It'll give you 3200+ good rounds and never needs to be retuned or touched.
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Relatively new to reloading and working up a 6gt load for my Bergara Premier Comp. I'm at around 85 rounds in, so realize things may change as far as velocity as the barrel breaks in.
Alpha brass
108 Hornady ELDM's
CCI 450 primers
Varget
I got pressure signs at 33.3 grains, which was 2881 fps. My concern is these pressure signs were ejector imprints/deformation of brass and a heavy bolt. But looking at all the brass, even down at 30 grains, I'm getting shiny marks from the ejectors. Is this normal...possibly from it being virgin brass? I obviously know the 33.3 is too hot, but it's hard to pick where the marks get "worse". Seeing many on threads like this getting higher loads, so also wondering if there is anything I may be overlooking on what I'm doing.
Alpha brass
108 Hornady ELDM's
CCI 450 primers
Varget
I got pressure signs at 33.3 grains, which was 2881 fps. My concern is these pressure signs were ejector imprints/deformation of brass and a heavy bolt. But looking at all the brass, even down at 30 grains, I'm getting shiny marks from the ejectors. Is this normal...possibly from it being virgin brass? I obviously know the 33.3 is too hot, but it's hard to pick where the marks get "worse". Seeing many on threads like this getting higher loads, so also wondering if there is anything I may be overlooking on what I'm doing.
Alright that’s I’m doing. Just touching the lands and not using jam as a measurement.
I’m going to use H4350 and start at 34.5grains. I’m running a Custom Rifle Barrel.
I have in the last few years seen a couple of rifles that leave ejector marks. Leaving ejector marks when a brand new, empty case is chambered and then extracted/ejected. I believe it is caused by a fairly strong ejector spring and a sharp edged ejector button. Heavy bolt lift and unusual expansion just above the case head are better indications of high pressure.
I own a rifle (MPA with Curtis action) that will mark a case with the ejector.
No marks just chambering and ejecting without firing. And at least on average, it gets more pronounced as load gets hotter. But no definitive marks that indicate this is the danger level compared to the previous loads. At least until I got some heavy bolt feedback and saw some peeling of the brass which occurred at the same time.
Going back off 0.5 grains from that load and do another ladder now that I have fire formed the brass. Realize things will change and maybe there is some affect from the brass not gripping the chamber as well when it's virgin???
I have not tried the MDT, however I have tried the Magpul, Ruger, and Amend2 poly mags with a Tika T3X in a KRG Bravo and they are a no go. The feed lips hit the edge of the Tika magazine cut on the bottom of the action. I can't file enough off the outside of the mag feed lips and don't really want to "relieve" the magazine opening on the action.
A little side project that I wanted to mess around with this winter was to see if I could get the remaining 95gr Nosler BTs (from a previous .243 Win project) to shoot out of my 6GT barrel.
I am also using N150 as the powder because I have 6lbs of it still, and no real project for it. It isn't as temp stable as others, so I'll have to keep that in mind as I'm messing with this stuff in the winter.
My goal is 3K FPS minimum, and 2/3 MOA @ 300 yards for 5 shots at least twice consecutively.
Doubt I'll hunt with it (it's a heavy ass AT-X), but so what? Itll be fun for me and I have a surplus of components...if that is possible.
Loaded 15 rounds and tried an uber-basic seating depth test today, starting at .030 and going to .075 in .015 increments. Just shot (3) groups of 4, and (1) group of 3. I did warm the barrel up. I shoot these in backwards order too (short to long)...Basically because if something shoots lights out all I have to do is seat the next group in a little bit and try to duplicate the results.
Anyway, .075 was UGLY. Well over MOA and vertically strung. .060 double grouped on me, then .045 and .030 hovered around the half-minute mark. Velocity for the two groups I recorded was right at my minimum with single digit SDs. I should mention here that my barrel has already done well with N150 and the 105 Hybrid at a similar charge weight, so this wasn't a shot in the dark.
It's a start. I'll load up some more in that seating depth window and play with charge weights a touch next. We'll see if it falls apart on round two.
Anyway, it's not a common/popular venture, but I figured I'd share.
I am also using N150 as the powder because I have 6lbs of it still, and no real project for it. It isn't as temp stable as others, so I'll have to keep that in mind as I'm messing with this stuff in the winter.
My goal is 3K FPS minimum, and 2/3 MOA @ 300 yards for 5 shots at least twice consecutively.
Doubt I'll hunt with it (it's a heavy ass AT-X), but so what? Itll be fun for me and I have a surplus of components...if that is possible.
Loaded 15 rounds and tried an uber-basic seating depth test today, starting at .030 and going to .075 in .015 increments. Just shot (3) groups of 4, and (1) group of 3. I did warm the barrel up. I shoot these in backwards order too (short to long)...Basically because if something shoots lights out all I have to do is seat the next group in a little bit and try to duplicate the results.
Anyway, .075 was UGLY. Well over MOA and vertically strung. .060 double grouped on me, then .045 and .030 hovered around the half-minute mark. Velocity for the two groups I recorded was right at my minimum with single digit SDs. I should mention here that my barrel has already done well with N150 and the 105 Hybrid at a similar charge weight, so this wasn't a shot in the dark.
It's a start. I'll load up some more in that seating depth window and play with charge weights a touch next. We'll see if it falls apart on round two.
Anyway, it's not a common/popular venture, but I figured I'd share.
Just reading all of the chatter about the poly AICS mags, which ones were working for you guys in the Tikka? I think someone said the Amend2 worked great, but someone else mentioned no go? I just bought a Grenade Chassis from MPA to throw in my barreled action and of course the CTR's are a no go. Anyone try CA's poly AICS?
For the ones that are working for you guys, any of them longer OAL than SAAMI? Meaning, I'll swap to .308 during killing season and run them long.
For the ones that are working for you guys, any of them longer OAL than SAAMI? Meaning, I'll swap to .308 during killing season and run them long.
I noticed not many reported using 108 ELD M
That’s what I can find local
Using Varget
GAP Hornady Brass and dies
I would sure appreciate some results with the 108 eld
Or if I’d be better off to try another bullet
That’s what I can find local
Using Varget
GAP Hornady Brass and dies
I would sure appreciate some results with the 108 eld
Or if I’d be better off to try another bullet
In my experience 108 eld's will shoot well using the same powder charges as other 105-110 grain bullets and a seating depth between.035-.060 jump is also a good place to start.
Piss off! What brass? I shot 109s with 32.8 of Varget on Alpha brass and BR4s after talking with GAP at their range. Was shooting 34. Even George said "thats on the hot side". But I sure wasn't seeing those velocities.
Alpha. Actually last weekend I discovered another load that showed me better results than H4350 and Varget…. RL 15.5. Shot a 5 shot group @ 300yds .631 then shot this 10rd just to confirm. Very happy with the results of RL 15.5
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if anyone is shooting a Custom Rifle Barrel with 109’s and h4350. I would like to know what charges you found that worked well. I’m at 100 rounds and about to start some load development. Using Alpha Brass with 109’s and have a ton of h4350.
Start at 35.5 and work up in .5 grain steps till you hit the velocity you want to be at. Usually you'll have a good one around 36-37 grains.
In the three barrels I’ve got some data on (a Bart 7.5, a Krieger 7.5, and Krieger 7 - all 26”), 35.5 ends up about 2820-2850 with a 109, for what it’s worth.
I ran the Bart up to 37.0, but best groups and velocity spreads were below that. But that was 2930 or so, I was targeting 2850, so lower made more sense for me.
I ran the Bart up to 37.0, but best groups and velocity spreads were below that. But that was 2930 or so, I was targeting 2850, so lower made more sense for me.
This was is my plan. I’m at 100 rounds. First CRB barrel so trying to figure out when it’s steady enough for load development.
36.5ish. probably going to bump up this season to about 2900 fps. H4350 es/sd seem to tighten up with the gt at higher velocities. I hypothesize it's due to case fill efficiency.
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There are a few older posts here about N150 but is anyone using N150 currently and is it a 1:1ish replacement for Varget?
It will be very close in the 6GT for the same velocity from my experience... in the 25GT it's still close but I need about a grain more varget to match.
36.8 gr H4350, 109 hyb jumping 40k, Cci450 in alpha brass. This is a 24in 7.5tw ace rem varm with a Scythe-Ti supressor, zermatt TL3. 400y 10 shot group. The low impact was the slowest of the 15 on chrono(shot 5 Rd zero confirmation prior) there was some suppressor mirage through the string as I shot all 15 rounds in prob 5-6 minutes in 30 degree weather. ES isn't great but it'll do.
That was unsuppressed.
It's 19f right now. I started warmer and it's only down 40fps.
That interesting, the listed post above I showed a 15 shot string, cold bore, suppressed and my first round fell inside the 23fps es range, it wasn't the slowest round either. I typically see a cold barrel cold suppressor 1st round be slow by 30-50fps. I know a handful of shooters who run suppressed during team matches, and they load their first round with a higher charge compared to the rest for the stage to keep velocity the same. I did it for my hunting rifle as I experienced it there too. However I have not experienced it with my 6gt and that suppressor combination.
Today I did my best to keep it from fully cooling. No big first round dips. All shot suppressed. It was 24 degrees by the time I was done. .2gr gets me back to the velocity I had when it was in the 50's. I'm guessing this is a combination of temps and throat erosion. For sure there is temp instability, It was a lot worse two weeks ago when I wasn't focused on keeping the gun warm. Yesterday it was warmer but 10mph to 20mph that cooled the gun down quick.
