.020 from lands puts the bullet too far out? 308 rem 700p

I have a 12 twist so i have to stay with 175 tmk
Rem 700p build in aics. If i had known i would have gotten the 5r, was almost the same price, i though that the p was better.

Oh well when the barrel is going to be shot (if that ever happens) ill get a custom barrel made in 10 twist i guess.
 
I just did some testing today with 168 HDY BTHP (I still have a few hundred left to shoot).
Did tests at 200Y with a bipod and a bag, nothing super fancy about minimizing group size, relaxed regular shooting to test velocity and average groups.

43.0 H4895, no crimp, same headstamp cases, measured to a relaxed +- .02 grains (plus the scale error of .02 itself)

Test 1: .020 off lands (2.914 really long COAL).
AV 2775, ES 27, SD 9 Group size: 1.4 MOA, and if you add the flyers it's 1.8MOA, so strange thing is that it had more consistent velocity but shot poorly.

Test 2: 2.800 std COAL
AV 2807, ES33, SD13 Group size: .8 MOA, no flyers. More variation in velocity but much tighter group.

I got some stiffer extraction with the highest velocity shots, so I'm probably at max with 43.

So I think that I will keep at at STD COAL because it seems to shoot well, and I'll load tune from 42.0 to 43.0 and see how it works.
Opinions?
 
Today's rifles have longer throats, there has to be enough room in the chamber for the cartridge and the company lawyer.
My Savage .223 with a 1 in 9 twist has a longer throat than my AR15 rifles do.

Remington has a particularly tall lawyer. For plinking, 150 is enough.

The Savage has a deep throat so as to take the Sierra 80MK.
 
I just did some testing today with 168 HDY BTHP (I still have a few hundred left to shoot).
Did tests at 200Y with a bipod and a bag, nothing super fancy about minimizing group size, relaxed regular shooting to test velocity and average groups.

43.0 H4895, no crimp, same headstamp cases, measured to a relaxed +- .02 grains (plus the scale error of .02 itself)

Test 1: .020 off lands (2.914 really long COAL).
AV 2775, ES 27, SD 9 Group size: 1.4 MOA, and if you add the flyers it's 1.8MOA, so strange thing is that it had more consistent velocity but shot poorly.

Test 2: 2.800 std COAL
AV 2807, ES33, SD13 Group size: .8 MOA, no flyers. More variation in velocity but much tighter group.

I got some stiffer extraction with the highest velocity shots, so I'm probably at max with 43.

So I think that I will keep at at STD COAL because it seems to shoot well, and I'll load tune from 42.0 to 43.0 and see how it works.
Opinions?

Velocity ES was high because of a lack of neck tension. See if you can get more. neck sizer with expander button removed.
 
I have a 12 twist so i have to stay with 175 tmk
Rem 700p build in aics. If i had known i would have gotten the 5r, was almost the same price, i though that the p was better.

Oh well when the barrel is going to be shot (if that ever happens) ill get a custom barrel made in 10 twist i guess.

You could maybe go a bit higher than 175. I have a 1:12" twist 700 Varmint, 26" barrel, and it gave me 1/2" groups at 100 yards with hand loads, 185 gr Berger bullets. Jerry from Mystic precision always gives me valuable advice when I buy from him. He was right when he recommended me the 185 Bergers, I'm sure he's equally right recommending you the 178 A-Max.
 
That's very possible.
I have 500 of the 175 TMK to shoot, and another 300 168 BTHP, so I should be good for the season. I don't think that I will shoot more than 800 rounds of 308 this summer.
Maybe try another bullet next year.
 

stop flooding the market with cool facts, it destroys the conversation and debate.......

as I posted in another thread yesterday, I have a long throated 6ppc, with about a sixteenth of an inch of bullet in the case I shot a 5 shot group that measures 0.145 center to center, neck length goes back to the days of lead bullets and the need to keep the bullet lube protected during transport, it's really not necessary with today's bullets other then to prevent run out and neck tenions, but both of these are easily done with other newer methods of reloading
 
Back
Top Bottom