So mid 37gr in this case. Do you have your own rule for a good load density? Like Hairy was talking about 95% and up is gtg.
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6gt
- Thread starter Dthomas3523
- Start date
Sell all of them. Go Sierra 110. Those bullets just work! Just about to rebarrel my 6GT now and gonna burn the new barrel out with S110’s. It ain’t broke and I don’t intend to try and fix it.
Pretty much. I like a full case, to when I shake a loaded round, I can barely hear the chink of the powder. Switching to DTACS and 35.8gr H4350 still gives me that as the boat tail protrudes quite a bit lower than a 109 due to long bearing surface.
For those of you using H4350, any of you have velocity’s around 2840fps using 109 Bergers and 37.3 grains. I’ve looked and haven’t seen any as slow as mine. I’m using an A&D FX 120i and a Garmin xero C1. The powder and primers came from new stock. I’m 100 rounds in, it’s shooting tiny groups but am questioning the velocity according to Garmin. Wondering if my Garmin needs recalibrated. Thanks
H4350
Alpha OCD Brass
CCI 450’s
Bartlein 26” barrel
.0.120 Free Bore
H4350
Alpha OCD Brass
CCI 450’s
Bartlein 26” barrel
.0.120 Free Bore
I will on Thursday, just figured someone on here may have experienced the same problem, thanks for the input.
That is "slow" er than most here are getting, but sometimes a barrel won't truly speed up until 150 - 250 rounds.
I would 100% not worry about it if your rifle is shooting small. I know your question was whether your Garmin is off, but I would trust that as well. You can always shoot at 600 - 800 yards and see if your drop from your calculator matches what you are seeing if you really want to verify.
Taking it back out tomorrow, also loaded up 20 rounds w/ Vaget to cross reference velocities. Thanks
I mean if someone at the range has a garmin or labradar, shoot a few and compare to your unit. There are defective products made. Every one I've been around has shot very close to known labradar velocity, like within 10fps or less. 37.3gr H4350 is a heavy charge, and if it's making the pressure it should be, you should be seeing flattened primer. Normal charges in my experience to have a 109 at 2850 should be around 36.2-36.6 depending on barrel length. My 28" tubes is 36.2 t 36.6 at 2910-2920.
Any powders you like better for 6gt? Care to share some 6gt data? I assume it is pretty much the powder that they say its equivalent too?
I dont own a 6GT I was just replying to your question asking if anyone is using MW powders from American. I do use MP610 (N550) from American in my 22GT with excellent results..
Has that shown decent temp stability Dom?I dont own a 6GT I was just replying to your question asking if anyone is using MW powders from American. I do use MP610 (N550) from American in my 22GT with excellent results..
Yes. I have had no issues with temp stability and I've shot it from 30F to 95F low and high humidity
I'm also shooting it in my 22BR with 85.5 and 90s with low single digit SD's, great speed and 0.25moa accuracy. It's been great.
That's good to hear, I have a ton of powder from american reloading and wanted to try some for PRS.
Does anyone have some data on 22" barrel with 115 DTACS? I've got a 22" with 170fb in the works and have 2000 dtacs so I'm curious which powders to try first.
Are slower Cooler powders still doable with a 22" and 115's?
Does anyone have some data on 22" barrel with 115 DTACS? I've got a 22" with 170fb in the works and have 2000 dtacs so I'm curious which powders to try first.
Are slower Cooler powders still doable with a 22" and 115's?
Took the 6GT out today, shot 3 groups with H4350 and 3 groups with Varget @200 yards. I would have to look at my notes but the velocities do seem to be increasing, round count is now at 150. Varget at 33.5 gr performed well and outperformed H4350 w/ SD’s, group size,and extreme spread. Varget at 33.5 gr averaged just over 2800fps, need to look at what others have posted to see if that’s below average too? I pushed Varget up to 34 grains and even though the velocities didn’t quite average H4350 velocities, I began having heavy bolt lift and smearing in the case head…..not sure why that would be. I also rushed and shot two 5 shot groups at 500 yards, I like the consistency between the two powders, they performed essentially the same. I didn’t have any more of the Varget 33.5 so I had to use the 34.0 gr. Nobody else at the range had a chrono to cross reference but I don’t believe it’s the Garmin. Going to load up some more Varget and get Strelok set up.
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I dont shoot the 115 DTACs or 6GT but I did plug your requested data into Quickload and here are your top powders for your combo..
22" barrel
6GT
115 DTAC
Not going over 6GT SAMMI max chamber pressure of 61999psi
These powders in the below list are all giving you the optimal 90% or more case fill and 99-100% powder burn in your 22in barrel... Powders at the top of the list will give you the highest velocity. IMR4350 and H4350, IMR4451, RE16, Varget probably your best options. Working up loads with these powders Id start 10% below the charge weight listed and work up.
Rl16 will net the most velocity per grain, however it's bulkier than H4350. I didn't realize you were running a 22" barrel. I'd say low 2800s is gonna be upper end of safe pressure, 34gr varget with 115 is warm.
Hopefully you have a 0.169fb chamber or that long bearing dtac is robbing capacity. If you're 120fb, I'd switch to a 109 Berger.
Hopefully you have a 0.169fb chamber or that long bearing dtac is robbing capacity. If you're 120fb, I'd switch to a 109 Berger.
Thanks @padom Gonna have to check out quick load. I’m used to loading bulk for uspsa and 3gun.
Yes, 170 freebore. I think 2700 to 2800 would be fine
Yes, 170 freebore. I think 2700 to 2800 would be fine
Get it going 2820-2850 with H4350, seat it 15-20k off lands, it'll shoot. Has done just that in serval barrels for me. From a 26" is going 2820, 28" 2840, my 30" going 2880, accuracy never changed. All sub half moa at 400y. It's probably been one the easiest bullets to tune.
A .120” freebore works fine, there’s just less room to jump more than 10-20 thou off the lands, so .170 makes things a little easier if you’re the type that likes to play around with seating depth or use a bigger jump from the start. After ~1000rds a .120 freebore will be ~.170 anyways. 
It depends… things to consider are: How long is your bullet? How much do you subscribe to the “rule” about keeping the bullet’s bearing surface above the case’s shoulder/neck junction versus treating that as a suggestion? I’ve pushed bullets deeper into the case to jump more and had good results, so in the end: if it shoots, it shoots.
It just has to fit in your magazine lol.
I’ll most likely just go with .170. I’m jumping my 140g hybrids 40 thou already anywayA .120” freebore works fine, there’s just less room to jump more than 10-20 thou off the lands, so .170 makes things a little easier if you’re the type that likes to play around with seating depth or use a bigger jump from the start. After ~1000rds a .120 freebore will be ~.170 anyways.
What size mandrel for 6mm? I have a SAC modular die coming for 6gt. They only have .242 or .240.5 in stock currently.
I've got a .241 Sinclair mandrel, if I was choosing of go for .2405. I would think there would be some spring back so you'd probably be getting .002 interference fit.
I currently have the 21st century turning arbors for 6.5cm and 223. Debating sticking to that separate step or combining with the SAC. I’m not sure on the pull through mandrel yet
Do you see any difference in decapping while you size vs decapping in a seperate step?
I've been running a SAC 6BR die for a long time. Mark sent me one to test when they were first being released. It's a nice die, works great.
I don't use the pull thru mandrel that goes in it, just a bushing to squeeze my neck down 0.004 under loaded... I then use a 21st Century turning mandrel to open neck back up 0.002 for a final 0.002 neck tension
I also load on a 550c and depending on the die I run a Mighty Armory decapping die in stage 1 and size in 3 and mandrel in the last station.
But for a lot of cartridges I run a LE Wilson SS FL Bushing sizing die, I use the decapping pin that's already in that die and size and decap all in 1 step in station 1.
So to answer your question, no it doesn't matter if you decap when sizing or use a dedicated decapping die
I have recently picked up a few different 21st Century black mandrels in sizes above and below my existing TiN turning mandrel for 223, 6mm, 6.5 and 308
Playing with different bushings squeezing the neck down and these 3 different mandrel for each caliber you can set your neck tension anywhere from 0.001 to 0.004 and anything in between.
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I think you don't get the full effect of using a mandrel step unless you do it in a separate step after the case has been sized. If a die could size a case the same exact way a standard FL die does and open up the necks in the same exact way using a mandrel die does, every single case would get stuck... there's no such thing as free lunch, SAC's die is just a different expander-ball design (and it's really only a "mandrel" in name only).
(Plus, FWIW, if you want to really get into the weeds, I've found there is a slight benefit to FL sizing and then waiting until after you've dry-tumbled all your lube off before you do the mandrel step. The cases get knocked around more than most know when getting tumbled, so the mandrel fixes the damage from tumbling and the leftover dust from the tumbling media provides a little lubrication for one's mandrel.)
I first started with DTACS a few years ago. The barrel I started them on had 1200rds on it. .120 freebore, my load ended up at .040 off which put me slightly below the neck shoulder junction. Ran them at 2775 in a 7 twist. Had impacts out to 1300 in matches. There’s no need to push them hard as they perform well at the lower velocities.
Anyone shooting 105s in a 20 or 22 in barrel? Curious on velocity. I want to run a short barrel 6 that'll do okay on velocity that burns less powder than my 6cm.
