6XC, RE-17 and the 115 DTAC Results

[rijndael]

I posted this on 6mmBR, but wanted to share it here as well. Preston and the guys at Surgeon sure can build a rifle. This is one of their rifles.



Well, I finally made it out to the range to test out some loads. My prior load was:

H4350 38.7 grains
.010" off the lands
115 DTAC
Wolf Primer

It yielded 2875 fps (26" Rock barrel). Much past that and I had ejector swipes and somewhat heavy bolt lift.

With my RE-17 testing, from 39.0 to 41.0 grains, I had about 30 fps for every .4 grain increase.

The POI for that 2 grain spread was very close together.

The two best loads were:

RE-17 39.4 grains
.010" off the lands
115 DTAC
Wolf Primer
2940 fps
5 Shots .250 CTC

RE-17 39.8 grains
.010" off the lands
115 DTAC
Wolf Primer
2968 fps
5 Shots .375" CTC

The circle aiming point is 1" across.

I began to get some very mild pressure signs at 40.2 and 40.6 grains, specifically some ejector marks.

The velocity averages from my testing:
<span style="font-family: 'Courier New'">39.0 39.4 39.8 40.2 40.6
2899 2940 2968 2996 3035</span>

I will head back later on to test some 20 round groups of 39.4 and 39.8 for ES and SD numbers, but so far it looks quite promising.

 

[Nocalphoenix]

Re: 6XC, RE-17 and the 115 DTAC Results

Fabulous, was this with the norma brass or did you form from 22-250?

 

[rijndael]

Re: 6XC, RE-17 and the 115 DTAC Results

I use Norma brass.

 

[psinclair]

Re: 6XC, RE-17 and the 115 DTAC Results

what is the twist rate on that rock?

ive been testing 105 vlds and 105 scenars with very good results. im shooting a 27" bartlein 1-7.5 twist 5r.
with 39.0 grs. of rl17 getting 3046 ave. e.s. is 16 fps.
i had a little better luck with the fed 210m primer. tried
wolf and cci br2s.

FYI, my 7.5 twist would not stabilize a 115 vld in temps below 18
degrees f.
mine is also a surgeon action in an a5 mac, s&b 4-16 pm II.

 

[rijndael]

Re: 6XC, RE-17 and the 115 DTAC Results

It's a 1:7.5 Rock, also a 5R.