6gt
- Thread starter Dthomas3523
- Start date
I am about to order them.
Alpha 6 GT brass is .013 Thick and about .269 Loaded.
.264 Bushing
.2405 Mandrel to get .003 Neck Tension
Just waiting for bushings to come back in stock. I have 1K once fired alpha brass I dont want to resize until i get the new SAC die with shoulder/neck bushing. Will keep shooting my old 10-12x fired alpha brass until it comes in stock.
Alpha 6 GT brass is .013 Thick and about .269 Loaded.
.264 Bushing
.2405 Mandrel to get .003 Neck Tension
Just waiting for bushings to come back in stock. I have 1K once fired alpha brass I dont want to resize until i get the new SAC die with shoulder/neck bushing. Will keep shooting my old 10-12x fired alpha brass until it comes in stock.
I have loaded from like 2700-3000 with the GT. The most consistent range seems to be 2900-2940. SD and ES shrink in that range for some reason. H4350 as well. I think I just run 36.1gr and send it.
Yea you will some some speed increases over a 2-300 round match. Generally about 20-30 fps over that range depending on how hard you scrub the barrel. Just throw a garmin on every 5 stages or 50 rounds or so to check and see if its trending.
I clean every 2 (one day matches) or every 2 day match so not more than 300 between. Pull the barrel at 2k.
in using a .266 and getting 2 thou -2.5 thou neck tension. No mandrel currently
SAC die, .263 bushing, .2400 decapping mandrel, yields .0035 neck tension. I started with a .265 bushing, but wasn't quite getting enough squeeze, and had some inconsistency in neck tension.
I just bought 3 boxes (500 ct ea) of berger 105 HT’s from brownells and they sent me 3 different lots. C’mon, man.
I’ve heard locals complain about noticeable velocity change and poi shift going from lot to lot with berger 105’s. If this is anomalous, please soothe my frustration lol. I did email
Brownells to let them know and to see if they would offer a swap or something. If I can load my magazine with bullets from different lots and experience no difference in POI across a PRS stage or PRS match, then there’s no point in me chasing matching lot #’s.
You could always randomly choose and measure 20 bullets from each lot. Might help to ease you.
Locals who? I can count on one hand the amount high enough quality shooters, they are worth listening to in the NOVA area.
Most guys do not worry about that. You cannot see nor perceive results downrange. I had a long discussion with Brian Litz about different measurements across lot sizes for some 105 and 109 hybrids a few years ago. He said as they change out machinery and tooling there is some variance, but the critical dimensions and surfaces are all the same. For instance the bullets may be .015 longer in this lot but the BTOG and bearing surface along with weight and SD are the same. So while one bullet lot may be slightly longer, they have the same POI out to the reasonable distance most shoot (1500 yards or so).
The main reason you shoot bergers other than their consistency, is they are not lot sensitive like some other brands.
sounds like I don’t have much to worry about, then. Im new to the sport/hobby…i’m trying to take the message and leave the mess wherever possible.
Are you shooting Quantico on 7/12? Jump into squad 8 and well take care of ya!
Shooting the uspsa Area 8 championships that weekend so i had to withdraw once i noticed. Handgun is my main squeeze - PRS is merely a side chick. A very expensive one.
Got to test out my new CRB barrel and H4350 and the 105 Berger. These are the first shot outs of the barrel just seeing what the powder charges will do. All 5 shot groups. started at 35 gn all were loaded 60K off.
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I was wondering if anyone has a powder they run that gives more case fill then h4350 with less velocity? I like running 112match burners at 2700-2750 and feel like i am not getting enough case fill. I probably should go to a shorter case like bra/brx or dasher, but i like the reliable feeding of the gt with standard mags.
I bet you N160 would fit that bill.
Full disclosure: I haven't tried it in the GT, but have in other cartridges. Typically takes more powder to get the same velocity in 6 and 6.5 CM as well as .260 Rem.
Why do you feel like you're not getting enough case fill? Are your groups too big? ES/SD too big? Poor velocity?
I find my 6brx running a 112mb at similar speeds has almost full case fill and is consistently more accurate regardless of seating dept/neck tension/charge weight. My 6gt seems to have a smaller node at the velocities i like running. Both will shoot similar groups, i just feel like the 6gt is getting close to where the powder can settle to the bottom of the case and have inconsistent burn and inconsistent pressure.
I don't have a personal load, but I bet you could give h4831-SC or H1000 a try
I think until this shows up in a measurable way, ie group size, ES/SD, etc, you're looking for an issue that isn't there. Also, if you're worried about powder settling to the bottom just store your loaded round on their sides.
I ran a quick test with N150 a little while back - slightly more case fill than Varget. SD was < 4 over ten rounds, and similar velocity at same charge weight. You don't need a full case to get consistency.
Shhhhhhhhh! We don't share how awesome N150 is in the GT. That's how all our supply dries up.
Having the powder settle to the bottom when the case is laying down is the problem. When the powder burns there is a path above the settled powder were it can burn in front of the main burn causing pressure issues. I dont recall all the correct terminology but it typically occurs below 60% case fill. The goal is to have a consistent burn rate, and with less case fill there is room for inconsistency.
Yeah, VV powders suck, stop posting about them.
Did I say SD < 4? Sorry, I meant, 40 or 400...
Completely understand your goal. But the issue with power settling and getting inconsistent burn as a result is pure theory and conjecture UNTIL it shows up in your shooting.
I load 32.34gr Varget with 108 ELD-Ms. No where near full case. My 10rd groups with a bipod/rear bag are consistently 1/2 moa or smaller with single digit extreme spreads.
I think for consistent ammo, you need a consistent and effective load process paired with consistent components more than you need a powder that completely fills the case.
edited to add: If you're just playing with powders for the sake of it and trying to find better results, do you, Boo.
Forthcoming price increases will help with stocks.. H4895, Varget, H4350 has been on the shelf pretty consistently at some retailers (Scheels) lately. Hopefully price hikes and a seemingly years long stretch of panic buying means inventories will be in a better place for the viht and H powders.
What's not a joke is that VV prices are about to go up... prolly to be on par w/ H, if I had to guess... I haz a sad...
I better get rid of the 50-60# sitting around then
I know the feeling. I am building more rifles just to shoot the horrific VV powders, it just keeps appearing on my shelf.I better get rid of the 50-60# sitting around then
Haven’t even started using n150 yet, I bought it as a Varget replacement but still have some Varget and shooters world left. I’m using n165 in my 7mm Saum with excellent results.
I'm about to do a 20in barrel, 120fb, prob run 95-105gr bullets. Just hoping to keep mv over 2750.
