6gt

[MDof2]

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.

Which is strange, and I wish I knew the science and techie shit behind it.
The Proof I'm running now barely sped up when I broke it in and started load dev for it, and it runs slower with the same charge as other 6GT barrels. Shoots lights out, I'm not complaining, but a steady reminder that every batch is different.

 

[NiteQwill]

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.

Why don't you just pick a speed and send it? I would stop load development and just shoot.

 

[BoulderE89]

Why don't you just pick a speed and send it? I would stop load development and just shoot.

Just to see which one makes better SDs. But if I’m picking only one and running it without due diligence it would be the 2850

 

[Jefe's Dope]

What AMP settings are you guys getting when melting Alpha OCD?

Just ran mine through the recommended 145.

 

[MDof2]

Most alpha OCD stuff is somewhere between 142 and 145 in Aztech mode.

 

[NiteQwill]

I use 145 on all my OCD and non-OCD brass.

It's the same code that Alpha themselves recommends.

 

[Gtscotty]

That's interesting, I burned up two of the Gap Hornady brass pieces when I started and got 130 for both. I wouldn't have guessed Alpha would be so different, 146 is about what I use for Peterson 6.5 CM.

 

[GoferDog]

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 found exceptional accuracy at 36.3 running 2970, I didn’t find pressure until I was North of 37.2. Don’t handicap yourself velocity wise!

 

[BoulderE89]

I found exceptional accuracy at 36.3 running 2970, I didn’t find pressure until I was North of 37.2. Don’t handicap yourself velocity wise!

I actually have always preferred low and slow! Gives me time to spot down range and In my personal experience, my guns just run better with it a little slower.

 

[BoulderE89]

The difference in tof between 2800 and 2900fps at 600yds is .02 seconds....you fucking superhero you ....

Then call me Batman cause I spend money on precision rifles like I’m a billionaire and have no super powers lol

 

[BoulderE89]

....starts off on Ruger precision rifle.....

Speaking from personal experience?

 

[Niles Coyote]

Just an update on my Straight Jacket Armory prefit 6GT that has 3650 rounds (now) fired through the benchmark barrel.

I went into a regional match with 3535 rounds on the barrel last weekend and a couple stages in I noticed a zero shift as well as low impacts at the targets that were 900+ yards. Once I got back from the match I verified my zero had moved, the velocity had also dropped about 40fps and my groups at 700 and 1000 had a few fliers that opened it's normal performance up considerably. 1000 yard group measured just over 12 inches counting the high and low fliers present.

So there you have it, the majority of this barrels life had modest loads launching 109 hybrids around 2830ish with the first 700 or so rounds loaded to 2940ish and the last 800-900 were 108 ELD's loaded to 2830ish. It has worn a suppressor for most of those ELD's, I'd guess about 600 of them were suppressed.

Just to note, I always patched out this barrel with kroil and/or hoppes gun oil after every outing and cleaned the chamber. It's had abrasives (JB bore paste) run through it around the 1600 round mark and then again every 700-800 shots.

**I'll add a throat erosion measurement here shortly**

The barrel has been pulled and replaced with a 223 barrel to be used for match trainer duties for now.
I'll be using my 6GT chambered by 5x5 precision that wears a 24" Bartlein 400 mod bb barrel on another impact action for matches from here on out.

 

[BoulderE89]

Update on the two nodes:

Top group is 35.0 grains
Bottom group is 35.6 grains

10 shots @ 35.0 grains of H4350
Ave - 2865
SD - 6.1

10 shots @ 35.6 grains of H4350
Ave - 2899
SD - 8.8

Looks like I’ll be running the 35.0 at around 2860

 

[MDof2]

The difference in tof between 2800 and 2900fps at 600yds is .02 seconds....you fucking superhero you ....

LOLzzzzz I was thinking the same thing. I just didn't say it!

 

[Jefe's Dope]

Most alpha OCD stuff is somewhere between 142 and 145 in Aztech mode.

I use 145 on all my OCD and non-OCD brass.

It's the same code that Alpha themselves recommends.

It's what came back when we sacrificed a case for testing.

 

[Jefe's Dope]

Update on the two nodes:

Top group is 35.0 grains
Bottom group is 35.6 grains
View attachment 7880779


10 shots @ 35.0 grains of H4350
Ave - 2865
SD - 6.1

10 shots @ 35.6 grains of H4350
Ave - 2899
SD - 8.8

Looks like I’ll be running the 35.0 at around 2860

35.0 for sure and you'll get a few more rounds out of your powder.

 

[rmfield]

Update on the two nodes:

Top group is 35.0 grains
Bottom group is 35.6 grains
View attachment 7880779


10 shots @ 35.0 grains of H4350
Ave - 2865
SD - 6.1

10 shots @ 35.6 grains of H4350
Ave - 2899
SD - 8.8

Looks like I’ll be running the 35.0 at around 2860

Wow! That's pretty fast for an 18" barrel. Or perhaps its slow for a 30"

 

[BoulderE89]

Wow! That's pretty fast for an 18" barrel. Or perhaps its slow for a 30"

Just right for a 26”

 

[rmfield]

So why didn't you say so?

 

[rmfield]

Don't mean to pick on you. Its just a point that needs to be made form time to time in reloading threads. If you leave out critical info, your post is useless.

 

[BoulderE89]

Don't mean to pick on you. Its just a point that needs to be made form time to time in reloading threads. If you leave out critical info, your post is useless.

I made note of it being a proof prefit in 6GT and so far as I know they only make 6GT prefits in 26 inches. But I didn’t specify so that’s my fault.

If I forget info just ask and skip the passive aggressive stuff lol

 

[Niles Coyote]

Hit the range last evening to verify my load. All are 10 shot groups at 700 from my 24" 5x5 Precision chambered and fitted Bartlein 400MODBB with 109 hybrids jumping .060". Looks like 32.5 grains of RL-15.5 is the winner.

 

[bfk4lyfe]

I need some advice. I'm about to start load development again since I ran out of Berger 109s. I'm switching to Barners 112s, which I've used before, and then will probably stick with Horandy 109s for the rest of the barrel.

I have an 8#er of H4350 and Varget, but only one to open one, which should I go with?

 

[MDof2]

I need some advice. I'm about to start load development again since I ran out of Berger 109s. I'm switching to Barners 112s, which I've used before, and then will probably stick with Horandy 109s for the rest of the barrel.

I have an 8#er of H4350 and Varget, but only one to open one, which should I go with?

Based on my experience (YMMV) H4350 being pretty resilient to heavier bullets (ala, 6CM/6.5CM, etc running 112's, 140, 147's, etc.), I'd probably start with that versus the Varget.

 

[rijndael]

I also agree with that. I have run SW Long Rifle, RE16, and H4350 in my GT with 109s and 115gr DTACs. I think those burn rates are more suited.

What freebore do you have to run those 115s in the GT? SAAMI? Or .160" ish?

 

[John Glidewell]

Hit the range last evening to verify my load. All are 10 shot groups at 700 from my 24" 5x5 Precision chambered and fitted Bartlein 400MODBB with 109 hybrids jumping .060". Looks like 32.5 grains of RL-15.5 is the winner.
View attachment 7881430View attachment 7881431View attachment 7881432

What velocities you seeing? I am running 33.6 of 15.5 with 105s in Wife's rig, getting 2960 out of a 27" X-caliber. I have tested and run N550 in mine, 35.8 is 2953 with 109s. Testing N555 tomorrow. QL says 37.8 is 2996 on same barrel time, so we will see. Surprisingly it is not compressed in alpha ocd brass. I loaded 37.2 to 38.4 in .3 increments and none of them are compressed, they all shake. QL has max at 39.2. This is such a fun cartridge and seems to run well with a bunch of powders.

 

[Niles Coyote]

What velocities you seeing? I am running 33.6 of 15.5 with 105s in Wife's rig, getting 2960 out of a 27" X-caliber. I have tested and run N550 in mine, 35.8 is 2953 with 109s. Testing N555 tomorrow. QL says 37.8 is 2996 on same barrel time, so we will see. Surprisingly it is not compressed in alpha ocd brass. I loaded 37.2 to 38.4 in .3 increments and none of them are compressed, they all shake. QL has max at 39.2. This is such a fun cartridge and seems to run well with a bunch of powders.

32.5gr should put me in the ball park of 2810 and 33.0 around 2835, IIRC, it's been a bit since I checked velocity but that also lined up with my drop at 700.

I really enjoy this cartridge too, prior to the GT I was switching calibers for matches on every barrel change but I see myself staying here for the foreseeable future. Varget, N150, RL-15.5 have all treated be well, StaBall 6.5, RL-16 and H4350 also work in a pinch but they don't seem to group quite as tight for me. Eventually I'd like to try out some N555 and a couple shooter's world powders but I haven't gotten that opportunity yet.

 

[rmfield]

QL says 37.8 is 2996 on same barrel time, so we will see. Surprisingly it is not compressed in alpha ocd brass. I loaded 37.2 to 38.4 in .3 increments and none of them are compressed, they all shake. QL has max at 39.2. This is such a fun cartridge and seems to run well with a bunch of powders.

Did you create your own Quickload cartidge file for the 6GT? I've played around with this by stretching a Dasher and increasing the volume, but have not been happy with the results. BTW Neconos says that the 6GT will probably be in the June data update.

 

[John Glidewell]

Did you create your own Quickload cartidge file for the 6GT? I've played around with this by stretching a Dasher and increasing the volume, but have not been happy with the results. BTW Neconos says that the 6GT will probably be in the June data update.

Yes, 6x47 lapua, adjusted case capacity to 45.62, case length to 1.72 and my coal of 2.58 with 109s.

 

[Gtscotty]

Did you create your own Quickload cartidge file for the 6GT? I've played around with this by stretching a Dasher and increasing the volume, but have not been happy with the results. BTW Neconos says that the 6GT will probably be in the June data update.

Hmm, wish I'd known there was a June update on the way. I've been using Dasher as a base as well, and I finally ordered a QL update in April. I wish they would fix their 6.5 StaBall model while their at it, it's been way off my chrono in every cartridge I've tried.

 

[rmfield]

I was told that the 6GT is "done" and probably in the June update, but cautioned to check back to make sure before I ordered. It would be nice if they would just publish what's in the updates. Also, they could not tell me when the June update would actually arrive either.

 

[John Glidewell]

Interesting results. Not surprised based on burn rates. Going to test the below loads tomorrow. Winner take all. Not testing N550 anymore, it is not temp stable. 35.8 gets 2947 but in summer heat can have significant velocity swings. 37.5 of N555 was 2890 with SD of 2.4 and .312" group. Loads are based on barrel times in QL.

N555 - 40.5 max
37.6 - 2897
39.3 - 3018

RL15.5 - 35.5 max
33.7 - 2937

I am thinking the N555 loads will be good back ups but RL15.5 looks like it might be big winner. I think @Niles Coyote might be on to something about the GT shooting tighter with faster burning powders. My Wife's GT is running RL15.5 and has shot more consistently over anything else I have tested to date. Both rifle builds are very similar. Both using OCD brass.

 

[Jefe's Dope]

How much jump are you guys going using for Berger 109 LRHTs?

 

[John Glidewell]

How much jump are you guys going using for Berger 109 LRHTs?

Mine likes .050 jump.

 

[MDof2]

How much jump are you guys going using for Berger 109 LRHTs?

Cloverleafs at .060". Both 105's and 109's from a .120 FB reamer.

 

[Niles Coyote]

.060

 

[Gtscotty]

Went with .080, although .10 shot about the same.

 

[MDof2]

.060

Same gunsmith too!

 

[Darkside-Six]

How much jump are you guys going using for Berger 109 LRHTs?

0.080 I’ve found that anywhere from 0.060-0.100 all work well.

 

[MDof2]

The beauty of the hybrids are they are incredibly jump tolerant.

 

[ArkansasShooter]

Has anyone worked up any loads for the new 109 eldm?

 

[Darkside-Six]

Has anyone worked up any loads for the new 109 eldm?

From the 2 people I know that did they basically kept the same load as their 109 Hybrids and just played with seating depth. We’re within 10fps.

 

[4O6shootist]

RL16 is an excellent powder for the GT. It works very well in the 6 or 22 Dasher, and the 6 or 22 GT. If I could get decent quantities of it I wpuld be running it in both my Dasher and GT instead of Varget for one and 4350 for the other.

Another excellent choice is Shooters World Long Rifle. But like RL16, is unobtanium.

Have you tried SW4350 in any these cases? It seems a lil slower than H4350/RL16.

 

[Jefe's Dope]

Just for future reference for others.

36.0g H4350
Berger 109 LRHT, .050" off the lands.
CCI 450
Alpha OCD twice fired, annealed.
26" Bartlein 1:7.5 rht, .120" freebore chamber

Yielded good results yesterday at Pawnee from 400 - 1000 yards.

Much thanks to those who advised where to start.

 

[John Glidewell]

Finally got back out to test RL15.5 in this rifle. I used the profile built for another rifle, but it was off a bit. Then my labradar quit working. 4 years of abuse lol. I borrowed one from a friend and was able to get out today. Top row is 10th firing on OCD brass. Bottom row is 4th firing on OCD brass. (Annealed every firing) QL has max at 36.5 and barrel time was 34.6 and 34.7 for the 2 lots of OCD at 2952 and 2954 fps. This barrel is 1st of 6 we have for our match rigs. X-caliber 3R 7.7 twist straight taper with target crown, no muzzle threads. Shouldered on TL3 bedded in Manners TCS mini chassis with ZCO 5-27. Interesting results.

 

[4O6shootist]

Finally got back out to test RL15.5 in this rifle. I used the profile built for another rifle, but it was off a bit. Then my labradar quit working. 4 years of abuse lol. I borrowed one from a friend and was able to get out today. Top row is 10th firing on OCD brass. Bottom row is 4th firing on OCD brass. (Annealed every firing) QL has max at 36.5 and barrel time was 34.6 and 34.7 for the 2 lots of OCD at 2952 and 2954 fps. This barrel is 1st of 6 we have for our match rigs. X-caliber 3R 7.7 twist straight taper with target crown, no muzzle threads. Shouldered on TL3 bedded in Manners TCS mini chassis with ZCO 5-27. Interesting results.

View attachment 7885187

I've got a bunch of rl15.5 sourced.....does it burn on the dirty side like 16 does?

 

[John Glidewell]

I've got a bunch of rl15.5 sourced.....does it burn on the dirty side like 16 does?

It is a little dirty, not as dirty as some of the N500 powders. Great powder for GT. Best out of all the powders I have tested so far.

 

[4O6shootist]

It is a little dirty, not as dirty as some of the N500 powders. Great powder for GT. Best out of all the powders I have tested so far.

Good to hear!

 

[BuLLet]

Some velocity testing today with another one of my 6GT's.

@reubenski I think I've lost count of the total now

GAP PPR 6GT

107 SMK, 34.5 grains of H4350
New GAP/Hornady brass, old cci 400

Series,16, Shots:,10
Min,2689, Max,2718
Avg,2702 ,S-D, 9.4
ES , 29

Series,Shot,Speed
16, 1, 2713, ft/s
16, 2, 2697, ft/s
16, 3, 2705, ft/s
16, 4, 2706, ft/s
16, 5, 2718, ft/s
16, 6, 2691, ft/s
16, 7, 2689, ft/s
16, 8, 2696, ft/s
16, 9, 2701, ft/s
16,10, 2710, ft/s
----,----,----,----

 

[BuLLet]

Stick it back in the safe, pull another out to shoot

Nothing really, dunno if I'd even work up a load specific to this rifle.

Velocity's are fairly close between the GAP cut chambers, all Bartlein's of course.

What are you going to do with that gun once you get a load sorted? Or is it wearing a ballistic test barrel?