6gt

[ghostrider_OneOne]

Also im using brand new alpha ocd brass with cci 450s, varget, and Berger 105 hybrid targets. What would be a good starting load powder wise? And a good stopping point on the ladder test for powder weight?

It's been my experience that performing a ladder test before barrel break in is a waste of time.
After 90 rounds my barrel sped up by 35fps. Some of the nodes I thought were good at 50 rounds were not as good as ones identified at 150.
Having said that Varget has some big and easy nodes. Save the throat erosion and load easy to brake in 32.5 is a good spot right around 2800fps.
My 2 cents.....

 

[dmitchell09]

I’ve read and googled a lot. I have 112 match burners and I want to try reloder 16. I’ve only seen info for 105gr. Newer to reloading and wanted to get an idea so I don’t mess anything up. Thanks

 

[John Glidewell]

Hmm, I call it weirdness because I've been loading a bunch of different chamberings for a while now, and I've never seen a bullet lot change jack pressures like that. For reference, that's the same velocity that 40.3gr (0.8gr more) of StaBall gave me at 80 deg (25 deg warmer). I've used two other lots of this bullet, and there was no noticeable difference in velocities between them.

A new lot of cases with significantly lower capacity could definitely jump pressures, but I checked the water capacity on these when I got back, and trimmed the same they *may* be 0.1gr less... not nearly enough difference to explain what I measured. That's why it's weird to me, the only other thing I can think of is maybe the new cases are significantly undersized until they get blown out in the first firing, and are changing the powder burn characteristics quite a bit? Still seems like a lot though.



This barrel only has 300-400 rounds on it, and has honestly been surprisingly picky, but I guess I can't rule out a ring. I've cleaned pretty regularly, but I should probably break out the bore scope and check things out.


I did try some RL16 (my all around favorite medium rifle powder if I had to pick one) with the 112gr. Groups weren't impressive at the lower loads, but started to come together at 36.7gr and 37gr. More work to be done in that area, but here were the (only one shot) velocities:

112gr MB, Hornady Gap cases, 450s, 60 thou off the lands. 23" PVA prefit.
RL16
35.8gr - 2,849 fps
36.1gr - 2,887 fps
36.4gr - 2,874 fps
36.7gr - 2,915 fps
37gr - 2,901 fps

I Chrono'd 37gr of RL16 in the old cases with an older lot of bullets on the same 35deg trip mentioned above at 2,895 fps. So same components shift as with the StaBall load above didn't really change much, certainly not a 70fps change.

@dmitchell09 this is on page 14 of this thread. I know there is more here too, so try going through this thread.

 

[Roksliding]

What kind of increase in speed (from a new barrel) have you guys been seeing with your GT??

I got-
107smk
33.8 gr Varget
Cci 450/alpha brass
.060 off
26” 1 in 7.5 Bartlein
@ 2880 fps with 80-90 rounds on the barrel…

The rifle just seems to be happy right there, (accuracy/consistency wise) so I’m gonna ride it out till everything settles….


Safe to assume I’ll be around that 2920 speed when the dust settles?

 

[MDof2]

What kind of increase in speed (from a new barrel) have you guys been seeing with your GT??

I got-
107smk
33.8 gr Varget
Cci 450/alpha brass
.060 off
26” 1 in 7.5 Bartlein
@ 2880 fps with 80-90 rounds on the barrel…

The rifle just seems to be happy right there, (accuracy/consistency wise) so I’m gonna ride it out till everything settles….


Safe to assume I’ll be around that 2920 speed when the dust settles?

Mine sped up a slight bit, and settled into 2885fps with 33,6g of Varget under a 105. Seems to be a fairly common node.

 

[Darkside-Six]

What kind of increase in speed (from a new barrel) have you guys been seeing with your GT??

I got-
107smk
33.8 gr Varget
Cci 450/alpha brass
.060 off
26” 1 in 7.5 Bartlein
@ 2880 fps with 80-90 rounds on the barrel…

The rifle just seems to be happy right there, (accuracy/consistency wise) so I’m gonna ride it out till everything settles….


Safe to assume I’ll be around that 2920 speed when the dust settles?

Mine sped up about 20-30fps.

 

[Juggerxxx]

This is recently with my third barrel. All the same powder charge of 35.9yr H4350 and 109.

First 20 rounds = 2816
At ~100 rounds = 2844
At ~175 rounds = 2880
At ~275 rounds = 2910 with one round as high as 2954 at this last match.
Not sure what it is now after the match and sitting with almost 500 rounds.

 

[Darkside-Six]

This is recently with my third barrel. All the same powder charge of 35.9yr H4350 and 109.

First 20 rounds = 2816
At ~100 rounds = 2844
At ~175 rounds = 2880
At ~275 rounds = 2910 with one round as high as 2954 at this last match.
Not sure what it is now after the match and sitting with almost 500 rounds.

You may have developed a carbon ring. I’ve been through quite a few barrels and have experienced them many times. Usually around 450-500 rounds. Give it a good scrubbing.

 

[Juggerxxx]

You may have developed a carbon ring. I’ve been through quite a few barrels and have experienced them many times. Usually around 450-500 rounds. Give it a good scrubbing.

There is a very good chance of that. I too need to clean the chamber and throat out every ~300 rounds to get rid of that carbon ring with my last two barrels. I can see it develop with a scope. I did scrub the hell out the barrel and throat last week but I had also done it around the 100 round mark too. My last two barrels stopped speeding up around the 400-500 mark and each time had seen around a 100fps increase. They were stable after that. Finally going to do an OCW in the next week or so to find out what she likes down her hole.

 

[NiteQwill]

What kind of increase in speed (from a new barrel) have you guys been seeing with your GT??

I got-
107smk
33.8 gr Varget
Cci 450/alpha brass
.060 off
26” 1 in 7.5 Bartlein
@ 2880 fps with 80-90 rounds on the barrel…

The rifle just seems to be happy right there, (accuracy/consistency wise) so I’m gonna ride it out till everything settles….


Safe to assume I’ll be around that 2920 speed when the dust settles?

I would keep it as is.

Current running 31.8 Varget with 109 LRHT. 40 thou jump. 2860 fps. This is my fourth barrel.

 

[ghostrider_OneOne]

What kind of increase in speed (from a new barrel) have you guys been seeing with your GT??

I got-
107smk
33.8 gr Varget
Cci 450/alpha brass
.060 off
26” 1 in 7.5 Bartlein
@ 2880 fps with 80-90 rounds on the barrel…

The rifle just seems to be happy right there, (accuracy/consistency wise) so I’m gonna ride it out till everything settles….


Safe to assume I’ll be around that 2920 speed when the dust settles?

I run two different load/bullet combos based on how extreme wind conditions are and max target range. Matches at my home range go out to 1450yards so use a 112MB for better reach.

105bthp 4166 32.4 2820fps when barrel was new, now 2852fps
112MB RL16 37.3 2910fps new, now 2955

I clean barrel after every shooting session. Just how I was trained. Clean barrel is the only predictable standard...IMO

Bartlein 26" 5r 7.5 to 1 stainless, Defiance action
1230 current round count. I saw a significant speed increase around 150 rounds.
Both loads shoot consistent 1/4" groups

 

[John Glidewell]

I have 70fps from first few rounds to 177 round count on this new barrel. The other 3 were about the same 50-100fps.

 

[PinesAndProjectiles]

Im looking to purchase an action for my 6gt build. Will a Bat Action: Mod M - Bolt Right - Dual Port - 1.55" Round - 308 Face work for my 6gt prs rifle build?

Isn’t the Bat M geared towards a long action?

I think the B action would be better for the GT if you’re set on running one.

 

[NiteQwill]

That's a very long barrel.

TriggerTech, Bix, etc.

Area419, APA, ACE, etc

 

[SD Carpenter]

Anyone use br-4 primers while we are on the topic? I picked up a few thousand but just been using up my 450’s. Anyone see a noticeable difference between the two?

It's what I use exclusively, work very well. Hell, everything works well with this

 

[SD Carpenter]

What kind of increase in speed (from a new barrel) have you guys been seeing with your GT??

I got-
107smk
33.8 gr Varget
Cci 450/alpha brass
.060 off
26” 1 in 7.5 Bartlein
@ 2880 fps with 80-90 rounds on the barrel…

The rifle just seems to be happy right there, (accuracy/consistency wise) so I’m gonna ride it out till everything settles….


Safe to assume I’ll be around that 2920 speed when the dust settles?

My modbb barrel hasn't sped up.... It's right around 2850 after 700 rounds same as the beginning of load development

 

[PinesAndProjectiles]

What would you guys recommend I have my smith cut my barrel at length wise? Its 29" but from what I've seen 26" is the go to for prs in the 6gt. Its a 7.5 twist.

Is this a PRS rifle? Bench gun? Hunting rifle?

 

[PinesAndProjectiles]

Prs rifle

If you plan on running a can, I’d go 24 or even 22”.

With a 26” barrel and a suppressor, you’re looking at 32” or longer and sticking that through a barricade can be a PITA.

If you’re running a break, 26” is probably the most common.

 

[PinesAndProjectiles]

Is there noticeable effects downrange between a 26" and 22" barrel. Id like to do what your saying but Im new to this and don't know what the downrange effects of going 4" shorter would be on the 6 gt

You’ll typically lose velocity with a shorter barrel.

 

[dimar1492]

Mine is like 22-3/8". I like the length as the intention is to run a suppressor nearly full time. 105 HVLD's shoot well at 2865 and 2930. 105 hybrids shoot well at 2900

 

[PinesAndProjectiles]

Im leaning towards going with a 24" That aint much of a velocity loss. Ive heard of people getting around 3000 fps out of the 6gt and im wanting to stay around 2800-2900 with Berger 105 hybrid targets.

This should be pretty easy. I’m pushing 112s at 2800 with a 24” barrel and a can with 36g H4350. And I’m not pushing it.

 

[dimar1492]

Thinking im going to purchase another can for this rifle since the one Im waiting on is for bigger calibers. Im thinking about going with the silencer co omega 300. What are you guys running on your 6gt?

I plan on running the KGM R-6.5

 

[NiteQwill]

Thinking im going to purchase another can for this rifle since the one Im waiting on is for bigger calibers. Im thinking about going with the silencer co omega 300. What are you guys running on your 6gt?

Area419 Maverick if you're shooting PRS. The recoil impulse is similar to a brake. I own a ton of cans (including an Omega) and while the Omega300 is good, it's not one I would suggest at all on a PRS gun.. KGM is a good alternative.

 

[Gtscotty]

I trued to 2920 fps on the 1,000yd steel on Friday, with 112gr Match Burners over 36.7gr RL16 in a 23" barrel. Went a little shorter because I shoot suppressed all the time and wanted to keep barrel + can under 30", figured I could still go at least as fast as long barrel Dasher with the slightly bigger GT case.

As for cans, I like my Nomads, I use the Nomad 30 on the GT a lot, and I use my Nomad Ti on some of my hunting guns. If I were doing it over, I'd get two Nomad Tis, as I don't have a machine-gun or run .223 SBRs hard or anything like that. I do have the E-brake that I mount to my Nomad 30 sometimes and it makes a difference.

Here's the rifle and can so you can see what the total length looks like.

 

[dimar1492]

Mine is like 22-3/8". I like the length as the intention is to run a suppressor nearly full time. 105 HVLD's shoot well at 2865 and 2930. 105 hybrids shoot well at 2900

Forgot to add that velocity for this rig with the factory Hornady 109 ELD-M load settles in around 2805 fps. The barrel is a Krieger 4 groove .237 bore

 

[Niles Coyote]

Berger load data.

 

[todd]

I'm running a 28' 1:7 barrel and getting 3004 fps with 33.66g Varget and 105 Target Hybrids.

What would you guys recommend I have my smith cut my barrel at length wise? Its 29" but from what I've seen 26" is the go to for prs in the 6gt. Its a 7.5 twist.

 

[Niles Coyote]

After a regional match, some practice rounds and now freshly cleaned, this Benchmark from Straight Jacket Armory is at 3535 rounds fired as of today. Group contains clean cold bore too

 

[sleeplz]

Area419 Maverick if you're shooting PRS. The recoil impulse is similar to a brake. I own a ton of cans (including an Omega) and while the Omega300 is good, it's not one I would suggest at all on a PRS gun.. KGM is a good alternative.

What size picatanny rail is on top of the spuhr mount?

 

[NiteQwill]

What size picatanny rail is on top of the spuhr mount?

It's not a picatinny mounts. It's a 10 mm spacer directly attached to the DPP mount Spuhr also offers.

 

[oldnewguy]

I realize this might be a dumb question, but I'm going back and forth between ordering a Dasher or GT.

It seems like a common Dasher load is a 109 Hyb running 2875-2900. Which sounds like where a lot of people are running their GT (with slightly more powder)

If that's the case, is it just about feeding and mag kits?

 

[NiteQwill]

I realize this might be a dumb question, but I'm going back and forth between ordering a Dasher or GT.

It seems like a common Dasher load is a 109 Hyb running 2875-2900. Which sounds like where a lot of people are running their GT (with slightly more powder)

If that's the case, is it just about feeding and mag kits?

Yep

I run 31.8 Varget for 2850. 34.2 Varget for 2960.

 

[oldnewguy]

Sounds like you can run your GT 50-75fps faster than a Dasher, if you wanted to

 

[NiteQwill]

Sounds like you can run your GT 50-75fps faster than a Dasher, if you wanted to

I run slower speed in the summer and higher speed in the winter.

 

[Juggerxxx]

I realize this might be a dumb question, but I'm going back and forth between ordering a Dasher or GT.

It seems like a common Dasher load is a 109 Hyb running 2875-2900. Which sounds like where a lot of people are running their GT (with slightly more powder)

If that's the case, is it just about feeding and mag kits?

I have to run a mag spacer kit in my AW mags for my Zeus and 6GT. Single stack mags will work fine without a spacer.

 

[Feniks Technologies]

I realize this might be a dumb question, but I'm going back and forth between ordering a Dasher or GT.

It seems like a common Dasher load is a 109 Hyb running 2875-2900. Which sounds like where a lot of people are running their GT (with slightly more powder)

If that's the case, is it just about feeding and mag kits?

You can shoot 6gt with noticeably cheaper brass with Hornady.

You’ll likely be at a lower pressure with the 6gt. As long as you keep the dasher under 2900 or so, should be fine. 2950 in a 26” barrel is pretty high pressure despite a lot of people running it (or used to anyway)

Currently, 6gt trends point to a bit more barrel life. Though that’s likely compared to everyone running their dasher at 2950 in the past. 2800 dashers probably last quite a while.

The recoil impulse is different if you notice that sort of thing. IMO, BR cases have a light and quick “snap” and 6gt, 6x47, 6cm have a “push”. Obviously, more velocity equals more recoil. But I prefer the push myself.

 

[Eurodriver]

Just shot my first regional PRS match with a borrowed 6mm. Placed in the top 10 out of 49 - I typically averaged around top 1/3 with a 6.5 so being among the jersey bois with nothing but a caliber change is impressive and I'm sold.

I have a 6GT on the way and a ton of RL16 and Berger 109s. Anyone having much luck with RL16? I know 4350 is the go-to but I have enough RL16 to last me years and would even be willing to sacrifice a bit of performance.

 

[ghostrider_OneOne]

Just shot my first regional PRS match with a borrowed 6mm. Placed in the top 10 out of 49 - I typically averaged around top 1/3 with a 6.5 so being among the jersey bois with nothing but a caliber change is impressive and I'm sold.

I have a 6GT on the way and a ton of RL16 and Berger 109s. Anyone having much luck with RL16? I know 4350 is the go-to but I have enough RL16 to last me years and would even be willing to sacrifice a bit of performance.

I've had great success with RL16 in this cartridge. I run 37.3 in alpha brass with cci450. I get 2940fps with ES below 20 and SD of 5. Consistent 1/4" groups. This is with a 112 MB. Hammer load for me. GAP PPR Defiance Tenacity 26" Bartlein.

 

[Eurodriver]

I've had great success with RL16 in this cartridge. I run 37.3 in alpha brass with cci450. I get 2940fps with ES below 20 and SD of 5. Consistent 1/4" groups. This is with a 112 MB. Hammer load for me. GAP PPR Defiance Tenacity 26" Bartlein.

I have a 26" Bartlein on the way as well, but a stockpile of 109s. Do you recommend the 112s? If so, why?

 

[ghostrider_OneOne]

If you have 109s stick with those. I didn't and couldn't find enough to shoot a full season. 112s for me have been very consistent. If you search old post you will find some bad reviews of what seems to be a bad lot of 112s. My experience has been excellent with a legit bc of .62. I also get good velocity with RL16. I haven't seen any reason to change. Earlier reviewers like norcal_vu have reported similar experiences. For me the 112 really shines past 700 yards in wind. My range has steel to 1400. It's also very windy. My 105s often require 2mils of wind at 900 where the 112 hits with 1.2. And this obviously grows with distance. The 1400 target is not uncommon to require 4 to 5mils wind with the 112. The 105 is off the reticle and held can only be done manually.

 

[Eurodriver]

If you have 109s stick with those. I didn't and couldn't find enough to shoot a full season. 112s for me have been very consistent. If you search old post you will find some bad reviews of what seems to be a bad lot of 112s. My experience has been excellent with a legit bc of .62. I also get good velocity with RL16. I haven't seen any reason to change. Earlier reviewers like norcal_vu have reported similar experiences. For me the 112 really shines past 700 yards in wind. My range has steel to 1400. It's also very windy. My 105s often require 2mils of wind at 900 where the 112 hits with 1.2. And this obviously grows with distance. The 1400 target is not uncommon to require 4 to 5mils wind with the 112. The 105 is off the reticle and held can only be done manually.

You west coast guys are a different breed At our match we were complaining about 4 tenths of wind at 990 yards lol

Appreciate the good info and quick response!

 

[RS14]

You west coast guys are a different breed At our match we were complaining about 4 tenths of wind at 990 yards lol

Appreciate the good info and quick response!

You forgot to mention it was a 6” target

 

[Eurodriver]

You forgot to mention it was a 6” target

That's a good point lol. Why does our MD hate us?

 

[RS14]

That's a good point lol. Why does our MD hate us?

It’s probably just because of Phil.

 

[BuLLet]

Tested Velocity on my 6GT load. Three different GAPs, same load.

05/22/22
GAP BAT 6MM GT

107 SMK, 34.5 grains of H4350
New GAP/Hornady brass, old cci 400
Series 7 and 8

Series, 7, Shots:, 5
Min,2732, Max,2765
Avg,2752 ,S-D,13.3
ES , 33

Series,Shot,Speed
7, 1, 2765, ft/s
7, 2, 2746, ft/s
7, 3, 2760, ft/s
7, 4, 2732, ft/s
7, 5, 2759, ft/s
----,----,----,----
Series, 8, Shots:, 5
Min,2705, Max,2739
Avg,2726 ,S-D,12.8
ES , 34

Series,Shot,Speed
8, 1, 2727, ft/s
8, 2, 2732, ft/s
8, 3, 2739, ft/s
8, 4, 2705, ft/s
8, 5, 2729, ft/s
----,----,----,----

GAP Templar II, MCS TCS Americana, 6MM GT
107 SMK, 34.5 grains of H4350
New GAP/Hornady brass, old cci 400
Series 10 and 11, 05/28/22

Series,10, Shots:, 5
Min,2703, Max,2728
Avg,2715 ,S-D,11.4
ES , 25

Series,Shot,Speed
10, 1, 2705, ft/s
10, 2, 2703, ft/s
10, 3, 2718, ft/s
10, 4, 2728, ft/s
10, 5, 2725, ft/s
----,----,----,----
Series,11, Shots:, 5
Min,2702, Max,2719
Avg,2712 ,S-D, 6.6
ES , 17

Series,Shot,Speed
11, 1, 2714, ft/s
11, 2, 2711, ft/s
11, 3, 2719, ft/s
11, 4, 2702, ft/s
11, 5, 2717, ft/s
----,----,----,----

GAP Tempest, 6MM GT, Manners TCS
107 SMK, 34.5 grains of H4350
New GAP/Hornady brass, old cci 400
Series 12 and 13, 05/28/22

Series,12, Shots:, 5
Min,2663, Max,2707
Avg,2688 ,S-D,16.4
ES , 44

Series,Shot,Speed
12, 1, 2691, ft/s
12, 2, 2683, ft/s
12, 3, 2663, ft/s
12, 4, 2707, ft/s
12, 5, 2696, ft/s
----,----,----,----
Series,13, Shots:, 5
Min,2680, Max,2703
Avg,2697 ,S-D, 9.6
ES , 23

Series,Shot,Speed
13, 1, 2702, ft/s
13, 2, 2680, ft/s
13, 3, 2699, ft/s
13, 4, 2702, ft/s
13, 5, 2703, ft/s
----,----,----,----

 

[BuLLet]

Well, it's more like 6 or 7 now...

Why not? Different actions, different stocks... kinda like socks.... One day red, one day blue, one day green

Why do you have three different GAP 6GTs?

 

[Feniks Technologies]

Why do you have three different GAP 6GTs?

Oh, you don’t know Mr. Bullet?

@BuLLet send him a pic of the AI safe. Lol

 

[BoulderE89]

Just did ladder test on a proof prefit for a lone peak action.

Using:
Alpha OCD brass
CCI 450 primers
H4350
Berger 109 hybrids

34.9 - 2848
35.1 - 2850
35.3 - 2869
35.5 - 2889
35.7 - 2889
35.9 - 2921
36.1 - 2926
36.3 - 2924
36.5 - Labradar didn’t read
36.7 - 2966

No signs of pressure on any cases. I have 3 pretty strong nodes here but I’m gonna play more with the 2850 and 2890 speed nodes and see what happens.

 

[briang7511]

Just did ladder test on a proof prefit for a lone peak action.

Using:
Alpha OCD brass
CCI 450 primers
H4350
Berger 109 hybrids

35.5 - 2889
35.7 - 2889



No signs of pressure on any cases. I have 3 pretty strong nodes here but I’m gonna play more with the 2850 and 2890 speed nodes and see what happens.

this is where i would look.

 

[Juggerxxx]

Just did ladder test on a proof prefit for a lone peak action.

Using:
Alpha OCD brass
CCI 450 primers
H4350
Berger 109 hybrids

34.9 - 2848
35.1 - 2850
35.3 - 2869
35.5 - 2889
35.7 - 2889
35.9 - 2921
36.1 - 2926
36.3 - 2924
36.5 - Labradar didn’t read
36.7 - 2966

No signs of pressure on any cases. I have 3 pretty strong nodes here but I’m gonna play more with the 2850 and 2890 speed nodes and see what happens.

I just switched to my third barrel and it happens to be a Proof. I was surprised how much faster the proof barrel is than the other two. I have to drop the charge a whole 1.0gr of H4350 to get the speed back down to 2840fps. Currently running 34.8gr with the 109 Berger and it hammers.