6gt

[Dthomas3523]

There’s a couple threads going on that pop back up from time to time. Now that the cartridge is pretty well understood and all the non load questions are asked, time to make sticky for loads and such.

My current:

109 berger 0.020 off
Cci 450
34.0 Varget
Hornady Brass
2950 fps

 

[verdugo60]

109 Berger
CCI 450
Hornady brass
35.5 grs H4350
2880 FPS

Even with virgin Hornady brass that I don’t do anything but load or run a mandrel through and load it is shooting great. Great feeding out of my 12 rd unmodified MDT AICS mag in an XLR/Bighorn. Only 1/3 the way through this barrel but besides the speed it’s lived up to the hype for me, I’m happy with it.

 

[buglum]

109 Berger
0.025" off
Alpha Brass
CCI 450
37.7gr VV N555 Powder (not much info out there on this powder but it works great)
2860 FPS on Labradar

 

[Juggerxxx]

109 Berger 35.7gr H4350 0.050” off the lands going 2880fps. CCi400 Hornady brass and using a G7 0.300.

 

[Olen_4504]

what barrel life are guys getting now that's it been out a bit?

My buddy said his took a dump at ~1000-1200rds he was pretty bummed.

another said he pulled his at 1800. but only because it was a good time to switch to his second GT barrel. he said it was still shooting well

 

[Dthomas3523]

what barrel life are guys getting now that's it been out a bit?

My buddy said his took a dump at ~1000-1200rds he was pretty bummed.

another said he pulled his at 1800. but only because it was a good time to switch to his second GT barrel. he said it was still shooting well

Was his reason for pulling it velocity loss or accuracy? Did he clean it down to the steel and verify?

 

[Olen_4504]

Was his reason for pulling it velocity loss or accuracy? Did he clean it down to the steel and verify?

the first guy pulled it cuz velocity dropped and groups opened up. and he couldn't get it back. not sure exactly what he tried. he just told me he has another barrel that's at 1400 and still going strong he just hasn't been shooting it lately.

the other guy only pulled it because he got another barrel in and didn't want to chance the 1800ct barrel to go on him in a match. he said it had opened up a little bit but was still under 1/2min

 

[Dthomas3523]

the first guy pulled it cuz velocity dropped and groups opened up. and he couldn't get it back. not sure exactly what he tried. he just told me he has another barrel that's at 1400 and still going strong he just hasn't been shooting it lately.

the other guy only pulled it because he got another barrel in and didn't want to chance the 1800ct barrel to go on him in a match. he said it had opened up a little bit but was still under 1/2min

I’d be pretty surprised if barrels don’t last at least as long as dasher.

I stopped running it earlier this year due to the alpha brass fiasco. But running it again now with hornady. I should burn out a couple barrels by mar/april.

 

[Olen_4504]

I’d be pretty surprised if barrels don’t last at least as long as dasher.

I stopped running it earlier this year due to the alpha brass fiasco. But running it again now with hornady. I should burn out a couple barrels by mar/april.

word. let us know how it turns out

 

[JLP.Payette]

108eld
Hornady Brass
36.5 H4350
2870 fps
24” barrel

 

[kriller134]

@Dthomas3523 are there any issues one needs to know about before jumping into this cartridge? I’ve heard pressure issues but I’m not sure if it’s good info or not.

 

[Dthomas3523]

@Dthomas3523 are there any issues one needs to know about before jumping into this cartridge? I’ve heard pressure issues but I’m not sure if it’s good info or not.

Only with gen 1 alpha brass.

 

[xocyrusx]

Berger 105 Hybrid
36.5 H4350
CCI 450
Hornady Brass
26” Barrel
2900 FPS

 

[Gulep001]

105 Berger Hybrid .070 off
CCI 450
Hornady brass (on 6th firing, pockets still tight)
34.0 Varget 2,990
33.5 Varget 2,930
33.0 RL-16 2,820
35.8 H4350 2,880
Stuteville Bartlein 26”MTU prefit.

 

[Coltonlrs]

Berger 109gr
3,000fps
Es 7fps
Sd 2.7 fps
26 inch patriot valley barrel

 

[verdugo60]

Berger 109gr
3,000fps
Es 7fps
Sd 2.7 fps
26 inch patriot valley barrel

purpose of this thread is to add load data to establish trends, etc. can you add your primer, powder charge, etc.

 

[kriller134]

105 Berger Hybrid .070 off
CCI 450
Hornady brass (on 6th firing, pockets still tight)
34.0 Varget 2,990
33.5 Varget 2,930
33.0 RL-16 2,820
35.8 H4350 2,880
Stuteville Bartlein 26”MTU prefit.

How do you like rl16? Are you maxing out at 33gn?

 

[Coltonlrs]

purpose of this thread is to add load data to establish trends, etc. can you add your primer, powder charge, etc.

Cci br-4 primers and hornady brass powder charge was 34.0 grains

 

[Gulep001]

How do you like rl16? Are you maxing out at 33gn?

I was actually running 33.5 RL16. Typo above. No pressure signs. Found the load from another 6GT thread just to see what it would give me and for data on other powders as back up. Worked great and never bothered trying another charge weight. I dont like to spend too much time chasing SDs and groups. GT has been really easy to load for. Reload it consistent and low SDs by default. I used to run it at 3,020. Now im backing off charge slowly, getting velocities slower and it still shoots. I see no advantage really in running it 3,000 + at PRS matches

 

[FCrifles]

Virgin Hornady brass
105 Hybrid
26" Rock Creek M24
.060" off touch
33.3 Varget
CCI 450
2920 fps

 

[kindabitey]

Alpha OCD brass
Fed 205M
37.0 gr VV N555
115 Dtacs at -.020
2775 avg es-17 sd-4.2 for 26 rounds (4 of the 30 round string did not register)

This is w/ 65 rounds on a new Stuteville 26" 7.5 twist. I expect it to speed up to around 2850ish.

 

[kindabitey]

what barrel life are guys getting now that's it been out a bit?

My buddy said his took a dump at ~1000-1200rds he was pretty bummed.

another said he pulled his at 1800. but only because it was a good time to switch to his second GT barrel. he said it was still shooting well

I pulled mine at 1950, but it was still shooting well and no velocity loss. I might stick it back on after I get a few more through the new one, and see how far it'll go.

 

[Olen_4504]

I pulled mine at 1950, but it was still shooting well and no velocity loss. I might stick it back on after I get a few more through the new one, and see how far it'll go.

Good to hear. Sounds like mitch just had a bad draw on that one barrel.

 

[Dooby]

Alpha (non-OCD) and Hornady Brass
CCI BR4
H4350 @ 37.75gr
26" 7.5tw Proof Comp. Contour (GAP Spec chambered by Straight Jacket Armory) - bbl @ ~900rnds
105Hyb - 3025fps
108ELDM - 3020fps

That Hornady Brass is pretty good. Going through it's 4th firing. I do get some cratering and ejector marks, but no heavy bolt lift or extraction issues.

 

[30cal user]

	6mm GT
	Bullet	Powder	Charge	Primer	Brass	CBTO	Velocity	BBL	ROT
6mm GT	105	Varget	33.5	450	Alpha	1.94	2932	30
6mm GT	105	Varget	34.1	450	Alpha	1.94	2979	30
6mm GT	105	Varget	34.2	205m	Alpha		3018	30
6mm GT	105	Varget	34.5	450	Alpha	1.94	3000	30
6mm GT	105	H4350	37	br2	Horn		3015
6mm GT	105	H4350	37.8	205m	Alpha	1.968	3017	30
6mm GT	105	H4350	37.75	BR4	Alpha		3025	26
6mm GT	105	H4350	36.5	cci 450	Horn		2900	26
6mm GT	107	N140	33.1	205m	Alpha	20 OTL	2884	30
6mm GT	107	Varget	33.4	205m	Alpha	1.967	2908	30
6mm GT	107	Varget	34	205m	Alpha	1.967	2971	30
6mm GT	107	H4350	37.8	205m	Alpha	1.967	3010	30
6mm GT	107	SW Prec	33.8	205m	Alpha	1.967	2909	30
6mm GT	107	H4350	38.2		Horn		3060
6mm GT	107	RL 16			Horn		3100
6mm GT	108	Varget	33.2	450	Alpha	1.94	2897	30
6mm GT	108	Varget	33.5	450	Alpha	1.94	2960	30
6mm GT	108	H4350	36.6	205m	Horn	70 OTL	2951	30
6mm GT	108	SW Prec	34.1	205m	Horn	1.987	2982	30
6mm GT	109	Varget	34.5	450	Horn		2950
6mm GT	109	Varget				65 OTL	2910	26	7.5
6mm GT	109	Varget	34	BR4	Horn		3000	26
6mm GT	109	H4350	37	cci 450	alpha		2900	24
6mm GT	110	Varget	34	450	Alpha	1.975	2917
6mm GT	110	SW Prec	34	205m	Horn	1.983	2905	30
6mm GT	110	H4350	36.9	205m	Horn	38 OTL	2950	30
6mm GT	112	Varget	33.4	br2	Horn		2915
6mm GT	112	Varget	33.5	450	Lapua	1.94	2900	30
6mm GT	112	Varget	33.9	450	Alpha	1.94	2890	30
6mm GT	112	H4350	36.6	br2	Horn		2932
6mm GT	112	STA ball	39.5	br2	Horn		2965
6mm GT	115	Varget	32.3	450	Alpha	1.94	2794	30
6mm GT	115	Varget	33.5	450	Alpha	1.94	2901	30
6mm GT	115	Varget	34.2	450	Alpha	1.94	2924	30
6mm GT	115	RL 16	36.9	450	Horn		2855
6mm GT	115	RL 16	37	450	Horn		2875		coated bullet
6mm GT	115	H4350			Horn		2970
6mm GT	115	N555	36.5			30 OTL	2854	26	7.5
6mm GT	115	N555	37	205m	Alpha OCD	20 OTL	2775	26	7.5	low rnd count

 

[drwood96]

Alpha OCD brass
Fed 205M
37.0 gr VV N555
115 Dtacs at -.020
2775 avg es-17 sd-4.2 for 26 rounds (4 of the 30 round string did not register)
View attachment 7526598
This is w/ 65 rounds on a new Stuteville 26" 7.5 twist. I expect it to speed up to around 2850ish.

What freebore are you running? I have .120 and 1k DTAC but read they sit deep in the case and cause issues.

---

It might be beneficial to post freeborn as well since there are two popular ones out there.

Standard .120
Heavy/long .170

 

[drwood96]

Common 6 GT Powders
•IMR 4166
•Varget
•SW Precision
•H4350
•RL16


From George, Updated 04-03-2020

AMP Aneal codes. Pilot. 73

Mk 1 STD mode use code 82

Aztec mode use 142 for Hornady, 141 for Alpha.

If you are going to analyze using Aztec use pilot code 073 C

These are COAL to the lands for various bullets. These were measured on brand new barrels with the OG reamer and the Current, JGS and PTG. there was a +/- variation of .005 either side, so reamers as well as bullets vary lot to lot. They will always vary a tad Chamber to chamber , Rifle to Rifle. . Back off .010 as a MIn.

103 Vapor Trail 2.560

105 Berger Hyb 2.585

105 JLK 2.590

108 Hornady ELD 2.545

110 H A Tip. 2.620

112 Barnes 2.605

115 Nosler RDF 2.545

115 DTAC. 2.580

In looking at these #'s the current .120 FB is still the best for the standard Reamer as it will work well for everything and is the best for 105-109 Berger Hybrids, 112 Barnes and the Hornady 110 Atip

If guys were wanting a specific chamber cut for 115 RDF, 115 Sierra, 108 Hornady ELD or 103 Vapor Trail a .170 FB would probably be ideal for those 3 bullets which GAP does have a .170 FB Reamer but Its only used on request.

 

[K-wal]

26” PVA Zermatt Origin
Virgin Hornady brass
109 Berger .040 jump
34.3gr Varget 2900 fps
Winchester primer
SD 2

I get some cratering, but nothing crazy. I have some CCI 400s I can try as well.

Break-in load
Hornady brass
33.5gr Varget
Hornady 108 ELD .020” jump
Winchester primer
No velocity data

 

[Dthomas3523]

What's the problem with that? I have 200x pieces alpha I picked up in March of last year. They appeared to have thinker necks than the Hornady I've been shooting.

Soft case head on some.

 

[NiteQwill]

Berger 109
37.6 H4350
0.020 jump
CCI 450
Alpha Brass
3000 fps from Hawk Hill 26" bbl

Berger 109
34.5 Varget
0.020 jump
CCI 450
Alpha OCD Brass
2921 fps from Stuteville/Bartlein 26" bbl (brand new, expect more speed)

Both are single digit ES and SD among continuous 10 shot groups.

 

[Kadams1563]

What's the problem with that? I have 200x pieces alpha I picked up in March of last year. They appeared to have thinker necks than the Hornady I've been shooting.

They show pressure signs easy. Ejector marks come very early. I just use them as a count of how many times fired lol.

 

[Kadams1563]

I wish they would replace my standard brass with the OCD stuff but it isn’t that big of a deal really. I just don’t load them extremely fast. Running a 108 with H4350 at 2980 without any issue.

 

[Dthomas3523]

You'd think alpha would make things right with their customers. I thought their Creedmoor cases were soft too so sold em. Maybe all alpha brass is soft? They had to OCD to get it to hold same psi as lapua/Peterson, hopefully they spread that through all their cases and it becomes standard.

Anytime I complained, I was told by alpha and their supporters it was my fault or the barrel had a tight bore (3 bartleins and 1 proof).

So......

 

[kindabitey]

What freebore are you running? I have .120 and 1k DTAC but read they sit deep in the case and cause issues.

---

It might be beneficial to post freeborn as well since there are two popular ones out there.

Standard .120
Heavy/long .170

I didn't add the freebore, because I have no idea what it is. It's whatever reamer Stuteville uses.
Honestly, I don't really care. I start at -.020 and as long as the bullet/powder combo is under 3/4" at 100, and ES is under 30 (at least 20 rds.) I'm off and running.

 

[short_mag]

Great information - thank you for posting.

 

[Darkside-Six]

what barrel life are guys getting now that's it been out a bit?

My buddy said his took a dump at ~1000-1200rds he was pretty bummed.

another said he pulled his at 1800. but only because it was a good time to switch to his second GT barrel. he said it was still shooting well

I’m just under 3k and mine is still going strong so not sure what’s wrong with his.

 

[Darkside-Six]

Hornady 110 A-Tips
.30 off
Hornady brass
CCI 450’s
34.5 varget 2950

Berger 109 Hybrids
.60 off
Hornady brass
CCI 450’s
34.5 Varget
2950

Berger 109 Hybrids
.60 off
Hornady brass
CCI 450’s
Varget 33.2
2870

Berger 105 Hyrbids
.60 off
Hornady brass
CCI 450’s
Varget 34.5
3050

Berger 105 Hybrids
.60 off
Hornady brass
Varget 33.8
2950

 

[Darkside-Six]

I wish they would replace my standard brass with the OCD stuff but it isn’t that big of a deal really. I just don’t load them extremely fast. Running a 108 with H4350 at 2980 without any issue.

They did make some newer 6GT brass that was the OCD. So far all the reports I’ve seen of people using it had no issues. Not like the original.

I’m waiting for more to come back in stock. Will probably switch to that from the Hornady. The Hornady has worked fine but after about 7 firings on it many of the pockets are starting to loosen on mine.

 

[357Max]

I just got 100 of the new OCD brass.
It’ll be a few weeks before I try it.
Working on getting the rifle together now.

 

[Desert Demon]

In lieu of CCI 450s, has anyone has success using CCI 41s or Federal Match primers. These are all I can find in the currently climate.

 

[blaster07]

A friend and I both got Gaprecision production class 6gt rifles a week ago. At 2499 they are a great deal I am using new hornady brass and dies with 100 of both 105s and 109s Bergers
winchester small primer
34grs Vit 140
2.590 OAL So far the 105s OAL is way more consistent than 109s with Hornady dies and smaller group at 300yds ,I am going to do more testing at 300. need to buy more bullets I can find 109s but no 105s. Whats others experience with 109s and 105s thanks

 

[Bolt Thrower]

For those full length sizing with bushing dies and Hornady brass - Any recommendations on bushing sizes?

GAP is recommending starting with 0.266" which seems small to me based on what has worked for 6.5 creedmoor Hornady brass. I am measuring (caliper) the neck wall thicknesses 0.015" on new 6GT brass and trying to achieve 0.002" neck tension. Planning to use 21 century turning mandel in an expander die.

 

[Dthomas3523]

For those full length sizing with bushing dies and Hornady brass - Any recommendations on bushing sizes?

GAP is recommending starting with 0.266" which seems small to me based on what has worked for 6.5 creedmoor Hornady brass. I am measuring (caliper) the neck wall thicknesses 0.015" on new 6GT brass and trying to achieve 0.002" neck tension. Planning to use 21 century turning mandel in an expander die.

Get a micrometer. I highly doubt it’s .015 neck.

If it is, you might want to look into turning the necks. You’ll be at .273 loaded on a .274 chamber.

 

[NiteQwill]

For those full length sizing with bushing dies and Hornady brass - Any recommendations on bushing sizes?

GAP is recommending starting with 0.266" which seems small to me based on what has worked for 6.5 creedmoor Hornady brass. I am measuring (caliper) the neck wall thicknesses 0.015" on new 6GT brass and trying to achieve 0.002" neck tension. Planning to use 21 century turning mandel in an expander die.

I use a 266 bushing.

 

[Bolt Thrower]

Get a micrometer. I highly doubt it’s .015 neck.

If it is, you might want to look into turning the necks. You’ll be at .273 loaded on a .274 chamber.

I use a 266 bushing.

Thank you. You're right, measurement was off and I do need to get a micrometer. Re-measured with some bias and it is probably closer to .0135-.014. The .266 bushing makes sense.

 

[Birddog6424]

Sure looks like the 109gr Hybrid likes the nodes at 2880 and 2950fps.

I guess a guy has to decide between chasing that higher node or running low and slow like some of the top shooters are trending..

 

[Dthomas3523]

Did George spec a new neck diameter? The print he posted online is 273. I hope he changed it, it was too tight to alpha brass in my opinion.

I think I misremembered. I thought it was a .274 and everything I have says .273.

I think they were trying to give everyone a place. Guys that neck turn wouldn’t have a ton of clearance, and guys that don’t would still have enough.

IMO, any 6mm reamer made for no neck turning should be .275

 

[tlsmith22]

The 6GT was the easiest to load develop I have personally ever seen. Running 34.4-35 of Varget has 8 FPS total speed difference with the 105 Berger. I settled on 34.5 Varget, Hornady brass, FGMM primers and honestly just picked a number for COAL to seat the bullets and never checked the jump. It shot single digit SDs and tiny .25” groups at 2954. I decided I would try a 109 with the same load and it was almost identical results but being slightly slower. I am running a 26” A-Team precision profile Mullerworks barrel (Impact prefit)spun up by BrIan Allen. I went ahead and ordered another barrel I was so well pleased with it.

 

[Darkside-Six]

Sure looks like the 109gr Hybrid likes the nodes at 2880 and 2950fps.

I guess a guy has to decide between chasing that higher node or running low and slow like some of the top shooters are trending..

I personally went with the slower one. Mine is 2870 but less recoil and can see trace better. Plus not as hard on the barrel.

 

[xocyrusx]

The 6GT was the easiest to load develop I have personally ever seen. Running 34.4-35 of Varget has 8 FPS total speed difference with the 105 Berger. I settled on 34.5 Varget, Hornady brass, FGMM primers and honestly just picked a number for COAL to seat the bullets and never checked the jump. It shot single digit SDs and tiny .25” groups at 2954. I decided I would try a 109 with the same load and it was almost identical results but being slightly slower. I am running a 26” A-Team precision profile Mullerworks barrel (Impact prefit)spun up by BrIan Allen. I went ahead and ordered another barrel I was so well pleased with it.

Just curious what is the COAL with?