I have 5lbs of IMR 4166 sitting here n a box so now I know wha I can try once my 6GT gets finished
I've settled on shooting Hawk Hills going forward. Not only for the performance but availability and contour (Heavy Comp).Im breaking in a new barrel with 32gr 4166 and 108bt bergers running 2780. They're jumping 70ish thou? Not certain but man does it shoot. My previous match load from old barrel with 109 lrht is shooting in the 2s and 3s. This hawkhill shoots better than the bartlein it replaced.
This is a hvy comp 7.5tw finished at 28" screwed to an Archimedes action. Had a 26" 7tw Marksman cut to a tl3 for the womans first prs rifle as well. Oddly her 26" is only 10fps behind my 28" with the same load. Granted I have 50k more freebore and hers the faster twist which probably the difference.I've settled on shooting Hawk Hills going forward. Not only for the performance but availability and contour (Heavy Comp).
Well, it's a good combination to start. I know several that use this combo with great results. My guess would be your best results are gone be in the upper velocity range with h4350 and 105. With my 26 inch Gt barrels, 34.5 - 35.5 of h4350 will get me in the 2850-2950 range. Most of my combos settle in around 2875 ish. I wouldn't be to concerned with barrel life, it's a 6mm after all. Like most others, It's probably gone die around 1500-2000.Have a 6gt barrel about to do some sort of load development on this weekend. I am using h4350, Berger 105 hybrids. Is there a optimal speed for barrel longevity? Only shooting this for PRS this season. I thought I read some where most are staying in the 2850-2950 speed for barrel life and a good speed? Help me out.
I don’t think so. I used the one it came with when I was running 109s.Did some searching and couldn’t find it but do I need a special stem for the 109 ELDMs? Running the RCBS match master set now
Ok I have root cause!HELP HUGE SHOULDER BUMP
Happy holidays everyone. I wanted to ask if anyone has any insight with what I am seeing that has me stumped.
I got my 6GT from GA Precision spring 2022 and what an amazing rifle. So far I have loaded and shot 100 new alpha brass for break in process with 105 Nosler RDF because it’s what I had. By the way 34.7 Varget gets barely over 3000 fps and about .2 MOA.
The issue is now I go to reload those original once fired brass and the shoulder bump is HUGE. I have tried two good die’s with Same result. Also using zero press.
Fired brass measures from 1.3040 to 1.3100 with SAC comparator
— When I run SAC die to contact shell holder I get .031 bump
— When I run Micron die to contact shell holder I get about .026 bump
I unscrewed the SAC die until I got the proper .002 shoulder bump and then measured gap between shell holder and bottom of die body and as expected it was about .032
THATS A WHOLE LOTTA BUMPIN’
not sure I have seen that much bump in contact with shell holders for other cartridges. The guys over at SAC are incredible to work with way beyond generous and offered to help troubleshoot so I gave them some examples of fired brass and my die to troubleshoot.
Are you all seeing this much bump when contacting the shell holder? Could something be wrong with my chamber?
Any help I would be thankful for
Thanks
Anyone here running Reloader 15.5 and notice the difference in felt recoil or am I losing my mind. My setup now is Impact in a Foundation with a 1-7 proof competition contour running 109 ELDM’s, 33.9 RL15.5 at 2880. Last year same action and Foundation but with a 1.75 MTU and 32.8 Varget at 2840 with 109 ELDM’s. I’m not saying the recoil felt is more but just feels snappier if that makes since.
Are both 236 bore? Perhaps the new barrel is 237 bore and reduces psi/velocity? Your speeds on new pipe do seem slow. Even comparered to my 7.5tw 237 bore barrels.Looking for some insight regarding a GAP PPR 6GT. I bought a PPR from GAP a little over a year ago. LOVE it! So much I decided to get another one. One for matches, one for training. My PPR in a serial number 300's last year of the tenacity action. I found a used PPR also tenacity action serial number 100's. When I bought my rifle I had another barrel spun up for it from GAP knowing I would burn through it and need another (side note I got 3100 rounds before significant loss of speed and groups opened up). So I'm at 540 rounds on second barrel. It hammers, just like first one. My loads are the same, nothing needed to change. So when I got the second rifle I was hoping things would be the same or close for reloading purposes since actions and barrels were the same (both tenacity, both bartlein 7.2 to 1, 26". The second rifle also hammers. I've very happy with it! What I can't figure out is why it is so much slower. The other rifle has app 600 rounds on it. I believe that to be true. I stripped barrel with Iosso and bore scoped it, beautiful condition! I did same to my second barrel on original rifle because I wanted to compare data and have an equal starting point. I generally shoot three loads. I will list them below and the differences. I will say it is clear I am going to have to do a completely new load development for second rifle, ES and SD's are just not even close to my acceptable range or that of first rifle. My guess is may be the second rifle had a larger free bore? Not sure why this rifle is over 100fps slower over almost all loads. It hammers, no doubt! I shoot a 3" group at 600 yards with Varget and 112 MBs, rifle is fantastic just different. Any ideas on what the difference is? I'm guessing it is obviously the barrel cut with different reamer but didn't realize (maybe wrong) they used more than one reamer on PPRs.
Loads:
112MB 37.3 RL16 alpha brass CCI450
original PPR 2908fps ES 16 SD 5.1 for 10rounds
2nd PPR 2802fps ES 35 SD 10.2 for 10rounds
105hybrids H4350 35.6 horn brass S&B primers
original- 2892fps ES 15 SD 4.6 10rounds
2nd- 2788fps ES 40 SD 12.4 10 rounds
112MB Varget 34.5 alpha brass CCI450
original- 2924fps ES 20 SD 6.3 10rounds
2nd- 2828fps ES 26 SD 8.6 10 rounds
Any ideas on cause of different speeds?
Really don't know what the bore size is. Just assumed since both were done by GAP same reamer was used, but don't know that for a fact.Are both 236 bore? Perhaps the new barrel is 237 bore and reduces psi/velocity? Your speeds on new pipe do seem slow. Even comparered to my 7.5tw 237 bore barrels.
They may have used the same reamer, but bore size is completely different.Really don't know what the bore size is. Just assumed since both were done by GAP same reamer was used, but don't know that for a fact.
Looking for help for a mandrel size for the 6gt. Never used a mandrel, other than what comes on redding dies. If u can even call it that. But, have a SAC die with Alpha OCD brass. Don't have a micrometer (ball). Any help would be appreciated.
Also, you still have to first use a bushing die to squeeze the neck down before using a mandrel to expand it. Typically people use a bushing that is .004 - .005 less than what your loaded round measures. There are a gazillion posts on this.Generally start at .002 less than bullet size, so .241
21st Century has excellent mandrels that come in
.0005 sizes. You have to have a mandrel neck sizing die to use them.
I started with the SAC 242 mandrel and that was not enough neck tension for my alpha brass so I an on the 241 now. Still testing but looks like I will stay there.Looking for help for a mandrel size for the 6gt. Never used a mandrel, other than what comes on redding dies. If u can even call it that. But, have a SAC die with Alpha OCD brass. Don't have a micrometer (ball). Any help would be appreciated.
how in the world can you shoot in those conditions? WAY WAY TO COLD for this TEXAN26" proof, .170 alpha reamer, alpha brass, FGMM primers and 110 Atips. View attachment 8063098
My previous outing was plagued by hang fires... just enough of a delay that you could feel/hear the pin drop before the discharge on each shot. On this outing I used a different primer and while it performed better I was still having hang fires about every 4th shot.
I'm going to clean my firing pin and firing pin channel and also change out my spring with a new one and see if it continues.
Temps were 16-18 degrees while shooting these.
how in the world can you shoot in those conditions? WAY WAY TO COLD for this TEXAN
That weather is just insane , us over here in Deep South Texas , it is in the low 40’s and it is freezing for us .We saw -21F overnight on Sunday and had a week straight of -10 in December. This is why SRPs are less than ideal.
That weather is just insane , us over here in Deep South Texas , it is in the low 40’s and it is freezing for us .
I haven't tried the 115 Bergers, 115RDF's shoot well in my barrel. Currently running 109 Berger's with 38.6 N555 for 2940fps. Not a hot load in my gun.Any one shoot the 115g berger vld’s ? I haven’t seen them much in this thread . I got a few pounds of n-555 and was thinking of trying the 115g vlds with that powder . Figured I’ll give it a try since I can’t find the 109’s to save my life .
@Niles Coyote you deserve a riteintherain kit for your notes. thanks for sharing. Feelin' cold for ya.
I pulled my GT barrel after 2,300 rounds and it was still shooting well.what barrel life are guys getting now that's it been out a bit?
My buddy said his took a dump at ~1000-1200rds he was pretty bummed.
another said he pulled his at 1800. but only because it was a good time to switch to his second GT barrel. he said it was still shooting well
I got 3100rounds out of Bartein 5r 7twist 26" barrel Mtu contour.I pulled my GT barrel after 2,300 rounds and it was still shooting well.
Nice! I could have ran it longer but I didn't want to take a chance of it going down during a match. My Bartlein barrel shat great when it was pulled.I got 3100rounds out of Bartein 5r 7twist 26" barrel Mtu contour.
Shot 2 loads
105,s h4350 35.6 cci450 2856fps
112mb RL16 37.3 cci450 2902fps