.308 Rem 700 AAC-SC Velocitites

[pinklbd]

I was wondering if any of you guys shooting this rifle have chrono'ed the Federal GM 175gr bullets. I know the box says 2600 fps, but I am going to think that it may be a little slower than that coming out of the 20" barrel. I am just trying to get a little more accurate numbers for my ballistic program. I will be getting a chronograph in the near future, just not before the comp I am going to be in next month.

Thanks Ben

 

[vtb]

175FGMM from SPS 20" 1:12 barrel: 785 ms or 2575 fps

 

[tylerw02]

My 700 AAC-SD 20" gets chronos to 2540 fps with Federal ammo. When I put the suppressor on it, it it speeds up to 2590, IIRC. The dope suggests its actually getting about 2570 fps unsuppressed, and ~2630 suppressed. My chronograph tends to read 30-50 fps slow on almost every rifle I own. When I was developing subsonic loads, it showed me as subsonic, despite there being an obvious sonic crack. So obviously, trust your field data over the chronograph.

 

[pinklbd]

Thanks for the fast responses guys!

 

[ccoker]

My 20" LTR with 44.2g of Varget and 175a does 2575 ands same POI as Fed match

 

[pinklbd]

What is the twist rate of your LTR

 

[pinklbd]

I have done some testing with varget. My Most accurate Load is 42grain shooting a SMK 168 gr. I had a pretty accurate load at 44 gr but not as good as 42. I am hoping to get a chrono soon so I can check my velocities. I think the 42 grains is going to be a little slow.

 

[gannon145]

ADL 26in. I just shot some 2 weeks ago and from 200-600 yards my adjustment reflected a fps of 2400. I'm trying to figure out what the actual issue is right now, but I too saw a much lower fps than expected.

 

[ccoker]

LTR is 1/12

45.3g Varget with 165 Sierra Gameking BTSP and Nosler Accubond were one ragged hole groups.