6gt
- Thread starter Dthomas3523
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Well when you're right, your right, it looks like my biggest problem with my rifle and loads was.... My crappy bipod technique.
Went back to front bags yesterday and only shot at 100yds since I was at the long range and there are no 200-300 berms there.
Might work on the Varget load a little more, I was running out of ammo towards the end but it showed some promise further out.
Back on the bipod, but here were the last two 39.5 StaBall loads, and three 34.5 Varget loads at 1,000.
I also tried 37gr RL16 25 off and it had some horizontal, but pretty narrow vertically and looked like it wanted to group, so I might try it 60 off and see how that goes. Other than that, it's time to load up a bunch with 39.5 of StaBall and get more practice in.
Hey all, following up on my previous question, does anyone have any thoughts on using RL16 to break in the new gun?
Based on my earlier post I picked up some StaBall, but I have limited supplies of StaBall and H4350, one of which I’ll use for the GT and the other for my 6.5cm. I hate to use up that limited supply just getting a couple hundred down the barrel before doing real load development.
I have one single lonely pound of RL16 that I don’t really have plans for. Seems like it’d be great to use with a light load to break in the gun. It seems to fall in the similar speeds as other 6.5 type powders, so should work safely for this. But I can’t find any info for it.
Anyone used it or have any thoughts for a safe, lighter load I could use with 108 ELDms to get some rounds on the gun without using up my valuable other powders?
Thanks
Based on my earlier post I picked up some StaBall, but I have limited supplies of StaBall and H4350, one of which I’ll use for the GT and the other for my 6.5cm. I hate to use up that limited supply just getting a couple hundred down the barrel before doing real load development.
I have one single lonely pound of RL16 that I don’t really have plans for. Seems like it’d be great to use with a light load to break in the gun. It seems to fall in the similar speeds as other 6.5 type powders, so should work safely for this. But I can’t find any info for it.
Anyone used it or have any thoughts for a safe, lighter load I could use with 108 ELDms to get some rounds on the gun without using up my valuable other powders?
Thanks
I wouldn't put a lot of brain damage into a 'break in load' then build another load after the barrel speeds up / etc. etc.
Find a powder you have a surplus of, load it, find your node and go. Tune when/if needed when the barrel speeds up.
I know several guys that run StaBall with excellent results. Same with RL16. I'd read the same about Superformance. Did OK, but not great.
4350 is a solid option as well.
This all being if you are unable to find more unicorn dust past the one pound it sounds like you have.
I was lucky enough to have a surplus of Varget when I started load dev. I loaded, found what it liked on velocity, and stuck with it.
Adjusted my kestrel slightly and still running the same load.
YMMV.
Thanks for the responses.
I have a few pounds each of H4350 and StaBall that I just picked up. The plan was to get the new gun broken in, then do a small test and decide which powder worked best for the GT and 6.5cm.
Since both supplies of those were limited and I’d read some guys going 150-200 rounds before really doing load development, I didn’t want to use up close to a pound of the limited supply for that. So thought I could use my surplus RL16 to get it going before going to the other powder.
But it sounds like that may not be such a big deal and I should just start with what I plan to use. I may be overthinking things.
I have a few pounds each of H4350 and StaBall that I just picked up. The plan was to get the new gun broken in, then do a small test and decide which powder worked best for the GT and 6.5cm.
Since both supplies of those were limited and I’d read some guys going 150-200 rounds before really doing load development, I didn’t want to use up close to a pound of the limited supply for that. So thought I could use my surplus RL16 to get it going before going to the other powder.
But it sounds like that may not be such a big deal and I should just start with what I plan to use. I may be overthinking things.
What you’re intending is fine. I’ve shit out a few GT barrels now. They have pretty good barrel life. Usually try and get 100 rounds through it so it has sped up and then do load development so you’ll be fine running the RL for the “break in”.
What are you guys getting for barrel life with sub 2950 loads? 2K? 2.5k? 3?
I am 700 into this barrel and wondering if I should order the next one now or if it can wait till next season.
I am 700 into this barrel and wondering if I should order the next one now or if it can wait till next season.
I pulled my last barrel at 3400 and it was still shooting great but o had to pull for piece of mind. Was running 2850 with 109 hybrids. I’d say even on the faster side you’ll get at least 2500 based on what I’ve seen from other friends shooting it as well.
I am in the same boat. Would like to save the Varget I have left. Would love to know if you tried RL 17. Thanks.
Jeff
Jlcichocki: I have decided that RE17 is probably too temp sensitive for my 6GT which will be used for various LR competitions. Otherwise, I'm sure it would work. Temperature sensitivity is the reason I quickly gave up on RE17 with another cartridge years ago. Too bad as I have a nearly full 8 lb jug of it. Fortunately, I found some VV N140 that will work well for my GT.
Fvcking hammer!
With th scarcity of Varget still, I see more and more H4350 results that are impressive.
Alpha OCD Brass
Cci400 srp
108gr ELDM 0.050" jump
36.3gr H4350
Happy with the results.
Cci400 srp
108gr ELDM 0.050" jump
36.3gr H4350
Happy with the results.
Hornady brass, fully preped. 205m primer. RL15.5, Berger 108 BT at .040 off lands. 5 at 100. TL3, Manners TCS, Leupold MK5 7-35, Bartlien mod400 lhgt 8.25 to 7 twist at 26"
I saw small velocity drop around 2500. But admittedly on that barrel I wasn’t documenting round count as well as temp/component changes that one should to be able to discern small velocity drop as throat erosion or something else. This is third barrel for me and I just rotate them to practice around 2500 to be safe.
I’d expect 2500-3500 for people who consider velocity drop time to pull. And probably 3-4k for people who use accuracy/precision as the indicator.
Everyone runs their barrels different. Some softer or harder than others. Do you go to the range and blast 200 rounds in 2 hours to practice for your competition, or do you shoot 10 rounds off a bench just so you can chat with your buds at the range and tell them how accurate your 6GT is? Both will have way different affects on the throat of your barrel. Everyone’s situation is different.
About ready to get my new barrel back. Can someone recommend some "break in" loads?
Edit: I have both Varget and H4350 and Berger 108 BT Target. Alpha OCD brass.
Also, can someone PM me their barrel break in procedure. To keep the thread on topic, please PM me. Don't post that info here. Thanks.
Edit: I have both Varget and H4350 and Berger 108 BT Target. Alpha OCD brass.
Also, can someone PM me their barrel break in procedure. To keep the thread on topic, please PM me. Don't post that info here. Thanks.
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Just how I treat my barrels, no real “break in”, I just wait for it to speed up and stabilize. Load up 100 rounds 36g of h4350 and jump those Berger 108s at .070”. Conservative shooting for 100 rounds even doing a jump test if you want. Then clean the barrel of carbon and copper. Then run your powder charge ladder.
You're a wizard if you made it to 2500 rounds before you saw any velocity drop off.
I burned up my first 6GT barrel in 1800 rounds running DTACs at 2850fps. Lost .120 off the lands in 1500 rounds. Had to rework the load twice to bring the velocity back into the 2800's.
But I've never had a barrel hold velocity through 2000 rounds. Even my last 4 BR barrels have usually dropped 70 to 80fps by the time I get to 2200'ish rounds.
I’ve never experienced any of that for 10+ barrels with 6br variants and 6gt.
6cm is only thing I’ve had drop faster than that. Sometimes as low as 900.
How is that possible. The lands erode, the characteristics of the throat changes with firecracking. These things cause changes in pressure and velocity. A loss of .035 to .050 off the lands by the time you get to 2000 rounds is fairly common. Its physics.
Not sure how its different for you. But ok..
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It’s not different for just me.
Most everyone is getting 2-3500 on their 6br variant and 6gt barrels. You’re one of the few claiming far less. So I’m not sure.
Also, the change doesn’t happen until a certain erosion of the neck area has “blown” out.
The lands don’t matter as much when you are jumping bullets.
Just like annealing hardly matters what you are seating or jamming into the lands. Where annealing show much more differences when you are jumping bullets.
Those are some interesting ideas. And forgive the skepticism, but its a head scratcher when one persons experiences don't jibe with anything you've heard before, or experienced yourself.
Glad your barrels are treating you so well..
Glad your barrels are treating you so well..
What’s head scratching?
When primer is struck, most of the time the bullet moves out a bit unless you have about tension to prevent that movement. This is prior to powder burn and such.
If it moves forward but doesn’t move into the lands, pressure is built up until it dislodges and moves across the jump and into the lands. With more pressure building at that point.
If the initial movement is enough to now touch the lands then the pressure builds immediately from that point until it’s enough to to push the bullet down the barrel.
This is the reason you hear people like David Tubb say he only anneals if he’s jumping and doesn’t anneal if he’s jamming lands.
The reason being, if jamming; the lands are the resistance for pressure build up the entire time. Therefore the neck pretty much doesn’t matter and can be very inconsistent and still see stable velocity numbers.
If you are not jamming, then the initial pressure build is based on resistance from the neck and therefore the necks need to be as consistent as possible.
So, if you have a large jump (will touch on that in a post immediately following) then the lands don’t matter much for your pressure and therefore aren’t going to be the reason your velocity drops.
The reason is the area around the neck gets to a point where it “blows” out a bit. That’s the initial drop in velocity. Over time as more blows out, it drops again and possibly “dies” at some point.
So, it’s now popular for long jumps in PRS.
The reason being that while it may not be the smallest groups, you get less change over the course of a 200+ round match.
Which is great. But, no one stops to ask “why.”
Well, that is very likely (without tons of money and equipment you can’t be 100% sure) due to the long jump prohibits the bullet from relying on the lands to build initial pressure.
Let’s say you’re jumping .020
How far does a bullet move forward on the initial primer strike before powder has burned enough to build more pressure.
If it moves .020, now you’re in the lands almost immediately building pressure.
After 150 rounds, your throat moves .006 and changes that.
Or let’s say you’re jumping .020” and the initial movement is .005. That’s 25% of your jump
And when the throat burns .005, your jump is now .030 and the initial movement is now 17%. That’s substantial
Now, let’s take a .070” jump. Bullet moves .005” on primer strike. That’s 7%
Throat burns .005” for .075. Your change still rounds up to 7%
That is likely why long jumps show less deviation across a 200 round match.
The reason being that while it may not be the smallest groups, you get less change over the course of a 200+ round match.
Which is great. But, no one stops to ask “why.”
Well, that is very likely (without tons of money and equipment you can’t be 100% sure) due to the long jump prohibits the bullet from relying on the lands to build initial pressure.
Let’s say you’re jumping .020
How far does a bullet move forward on the initial primer strike before powder has burned enough to build more pressure.
If it moves .020, now you’re in the lands almost immediately building pressure.
After 150 rounds, your throat moves .006 and changes that.
Or let’s say you’re jumping .020” and the initial movement is .005. That’s 25% of your jump
And when the throat burns .005, your jump is now .030 and the initial movement is now 17%. That’s substantial
Now, let’s take a .070” jump. Bullet moves .005” on primer strike. That’s 7%
Throat burns .005” for .075. Your change still rounds up to 7%
That is likely why long jumps show less deviation across a 200 round match.
Most people seem concerned with the green area. While yes that is important, the burned out barrel or velocity drop is from the area in red.
Which is why a barrel setback is only as minimal as needed to “freshen” the chamber.
This also means that unless you are comparing apples to apples (bullets, powder, case length, cleaning…etc) you can’t give a confident answer how long your barrel vs my barrel will last.
Which is why a barrel setback is only as minimal as needed to “freshen” the chamber.
This also means that unless you are comparing apples to apples (bullets, powder, case length, cleaning…etc) you can’t give a confident answer how long your barrel vs my barrel will last.
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I have no idea why you think I needed all of that explained to me. I understand the process quite well. The head scratcher is how you get to 2000 to 2500 rounds on a 6mm with "little" velocity change.
If you ever followed SoCal's initial 6GT thread on here when this round was in its infancy, you would see a fair number of guys pulled the first run GT barrels at <2500 rounds. Several never made it to 2k and expressed some disappointment. Though I do believe 2000 to 2500 rounds is fair barrel life for the GT, I certainly don't believe you'll get there without loss of velocity.
My BR barrels lose 70 to 80fps on average by the time they get to 2500 rounds. I've not had one surpass 3k in a functional manner. For me, that means will it survive a PRS match without losing velocity.. Nor have I heard of anyone running a GT or BR past 3k. Do I believe a guy could nurse a barrel that far? Sure. I know Morgun King ran a couple Dasher barrels to 3k running a nice easy Berger 105. But he pulled them at that point, and pulled all his other barrels sooner than that.. So that's not the norm for a competitive shooter. The large majority of competitive shooters are pulling a Dasher/GT type of 6mm at around the mid 2k round count. If nothing of significance had changed in the round characteristics by that point, why would anyone be swapping them?
I have no desire to spend pages debating it. I would rather just tell you I'm glad you are seeing good barrel life from your rifles and how you shoot them, and move on.
If you ever followed SoCal's initial 6GT thread on here when this round was in its infancy, you would see a fair number of guys pulled the first run GT barrels at <2500 rounds. Several never made it to 2k and expressed some disappointment. Though I do believe 2000 to 2500 rounds is fair barrel life for the GT, I certainly don't believe you'll get there without loss of velocity.
My BR barrels lose 70 to 80fps on average by the time they get to 2500 rounds. I've not had one surpass 3k in a functional manner. For me, that means will it survive a PRS match without losing velocity.. Nor have I heard of anyone running a GT or BR past 3k. Do I believe a guy could nurse a barrel that far? Sure. I know Morgun King ran a couple Dasher barrels to 3k running a nice easy Berger 105. But he pulled them at that point, and pulled all his other barrels sooner than that.. So that's not the norm for a competitive shooter. The large majority of competitive shooters are pulling a Dasher/GT type of 6mm at around the mid 2k round count. If nothing of significance had changed in the round characteristics by that point, why would anyone be swapping them?
I have no desire to spend pages debating it. I would rather just tell you I'm glad you are seeing good barrel life from your rifles and how you shoot them, and move on.
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There’s literally pages of guys here and on FB who say they get 2500 out of a dasher, 3k on a 6br
And variance claims of 2500-3500 on 6gt.
So, whoever “they are” you are not reading.
I pull a barrel as soon as I get a velocity drop.
That’s usually:
6cm 1k-1500
6br ~ 3k
Dasher and variants ~ 2500
6gt ~ jury still out on the average. Minimum 2500
We keep detailed records on velocity and have burned out more barrels than most.
Where did I say people aren't getting 2500 out of a Dasher?
And saying a 6GT will go 2500 at minimum to a guy who smoked his in 1800 shooting PRS.
Plenty of people have worn out 6GT barrels in <2200.
Look dude, I didn’t quote your post and basically tell you you’re full of shit.
You decided to come fuck around with something and now want to throw hands up when there’s pushback.
Here’s you saying you don’t believe you can get to 2500 on a 6gt without velocity loss. And saying you’ve never heard different.
Here’s a few screen shots that took 3 min to find.
So, again, read more before you make all encompassing statements and implying someone is exaggerating.
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If you two dipshits want to have a dick slinging contest, take it to PM.
No. I literally started this thread. So I’ll continue to post in it publicly.
I dont have your Google Fu skills. There's several guys in that 20 page thread who lost barrels at less than 2k rounds.
And funny that one of your quotes is one of the guys I shoot with all the time. His barrel last year didn't fare nearly so well.
But I'll confess to be surprised that so many people have similar experiences to yours. I havent seen a barrel perform in that manner for me. It remains a head scratcher I guess as to how guys are getting that many rounds down the pipe without velocity change.
Another lesson learned for me to keep an open mind..
And funny that one of your quotes is one of the guys I shoot with all the time. His barrel last year didn't fare nearly so well.
But I'll confess to be surprised that so many people have similar experiences to yours. I havent seen a barrel perform in that manner for me. It remains a head scratcher I guess as to how guys are getting that many rounds down the pipe without velocity change.
Another lesson learned for me to keep an open mind..
My apologies. This week has been a bit annoying for us.
So my fuse is short. Nothing personal.
Speaking of barrel life, I'm starting on my first 6GT with a Bartlein 400 Mod BB SS barrel that supposedly gets somewhere around double the life of their regular SS barrels. I bought it and paid the $200 premium for this "super barrel" because it was in stock (otherwise a 1 year wait). Its going to be interesting to see what my $200 actually gets me in the end.
I'm with you brother. I'm an RN that has been working around Covid patients for two years without catching it. Till 3 days ago..
My body aches, my head is killing me, and I'm picking stupid shit to argue over on the internet, and I'm not even right about it
But damn man, I do hope I get a little better barrel life out of these next two GT barrels. I have two 22 Dasher barrels and two 6GT barrels, all from Shawn at Hawk Hill, going to my gunsmith as soon as I go asymptomatic. It needs to impress me. I'm not sure what to think of it yet.
On that barrel, nothing crazy. I think I would run a Kroil patch or two through it, let it sit a bit. Then patch with Hoppes, dry patch and done.
Every 300 to 400'ish rounds on average.
I actually posted on this thread 6 or 7 months ago about a cleaning method I was told about by the Applied Ballistics crew. They were at the Big Sky Brawl in Montana last July I believe.
They turned me onto a scrubbing method they say increases barrel life and helps maintain better SDs on your bullets ballistic coefficient.
The biggest factor this year would be to not have the sun drag its balls across the Pacific northwest like it did last year. I shot two Pro Series and multiple one day PRS matches in 100 degree plus weather last year. I smoked that 6GT and a 22BR barrel. I went to the PRS Finale with a new load and 1500 rounds on my GT and it still couldn't hold it together for 250 rounds.
I believe they had a different Reamer at the beginning for the GT as well because there have been quite a few that have gotten 3k on their GT barrel. I posted somewhere earlier in this thread about me pulling my first GT barrel at just over 3400 rounds more or less for piece of mind. It was still shooting the same speed with no real muzzle velocity loss and still shooting tight groups. There are several guys in the Facebook group for GT shooters as well that got 3k.
I don’t even think I’ve seen anyone that hasn’t gotten at least 2300+ before they decided to pull it and those were more or less for piece of mind cause it was their first barrel on that cartridge. I’m sure if they’re running them hot…..north of 3000fps then maybe
I run mine right around 2850 ish and it’s been fine across 3 barrels now.
Thats amazing honestly. As I noted above, mine didn't make it to 2k. A guy I shoot with pulled his at 2k last fall, couldn't get a barrel, and ended up taking his Creedmoor to the Finale.I believe they had a different Reamer at the beginning for the GT as well because there have been quite a few that have gotten 3k on their GT barrel. I posted somewhere earlier in this thread about me pulling my first GT barrel at just over 3400 rounds more or less for piece of mind. It was still shooting the same speed with no real muzzle velocity loss and still shooting tight groups. There are several guys in the Facebook group for GT shooters as well that got 3k.
I don’t even think I’ve seen anyone that hasn’t gotten at least 2300+ before they decided to pull it and those were more or less for piece of mind cause it was their first barrel on that cartridge. I’m sure if they’re running them hot…..north of 3000fps then maybe
2850fps is where I was at as well with DTACs. By the time I shot my 3rd Pro Series match, it was down to 2770fps. Thats what the AB guys clocked it at in Montana. I shelved it after that to save it for the Finale and shot my BR. But it was toast.
Just a bad taste in my mouth I guess. Fingers crossed on the next ones.
Edit; I bought my own reamer for that from Manson. I want to say it's a .274 neck and .120 freebore
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