Strange happenings with LR-308

[nagantguy]

Hello gentlemen and ladies, I’ve been reading and taking advantage of the vast knowledge here for a while, went head and became a member. Thank you for having me!
I have a weird happening, or at least not normal . I’ve a recent home build 308 on a DPMS upper /bushmaster lower. Mega adjustable gas block, Areo Precision lower parts kit. A2 style flash hider. With Vortex strike Eagle optic.
I put this in the semi auto section if that’s not the correct place please feel free to move it.
anyhow with about every load I’ve tried- 147-175 grain projectiles over either 4895 or Varget powder, with the 16.25 inch barrel I didn’t expect nor was I building a precision rifle more of a deer hunter /300 yards plinker rifle.
The odd thing- everything I’ve fired factory or hand load goes about an inch and a half at 100 yards- the exception being 165 nosler Ballistic tips which go just under an inch at 100, but I get the same 1.5 inch at 200 and 300 yards as well, even the Nosler BT’s open you to about 1.5 at 200. I’m not complaining just never seen a rifle that was an inch and a half at 100 do better at longer ranges. This will be hell on wheels for deer- hogs and coyotes but I’m still scratching my head over inch and a half seemingly holding at 100-300 yards. Everything I’ve tried except the 147 grain projectiles have been under 2 inches . This far exceeds my expectations. Did I find a unicorn or is this a known phenomenon?

 

[CaptMerica60]

What barrel and twist are you using?

 

[bfoosh006]

What barrel and twist are you using?

This...

 

[hafejd30]

I’m not complaining just never seen a rifle that was an inch and a half at 100 do better at longer ranges

Short answer is that’s because they don’t

Maybe you had more focus on controlling the trigger, fundamentals, scope parallax etc at 300

Either way bullets don’t magically shoot 1.5 MOA at 100 and 1/2 MOA at 300. They don’t leave the point of aim and magically correct themselves back to it after stabilizing

Are we comparing shooting on the same day, same setup, same lot of ammo and components, same weather, barrel clean vs fowled, hot vs cold etc.

You or your setup contributes to the longer range accuracy somewhere in the process

I think a serious rifle smith/shooter (cannot for the life of me remember who it was but I’m sure someone here will know) offered a bunch of money for someone who could bring them a gun that would shoot tighter groups at longer range than it could at shorter range.

Comes up in the argument that longer bullets need time to stabilize “go to sleep” which is why they are more accurate at longer distances. Even if a bullet needed time to stabilize an unstable bullet traveling off its original path would continue traveling off that path once stabilized

Most of the time this is caused by scope parallax being off. Most people use it as a focus rather than what it’s intended for. When you shoot at 100 set the scope as you normally would, then move your head around behind scope without making contact with the gun. Do the same at 200 and 300 after setting up scope as normal. My guess is your crosshairs will move more in the scope at 100 due to incorrect parallax setting than it does at 200/300. Your reticle should look like it’s taped to the target when adjusted correctly. If it’s moving up/down/left/right as you move your head behind the gun it’s set up incorrectly

Another thing is some shooters have mental effects when they can see bullet holes on paper at 100 vs 300 etc. Can cause a person to over-concentrate resulting in eye strain amongst other things. Example is when you put 4 shots in one hole and try so hard to not bag the 5th one up that you strain your eyes, fatigue muscles etc in an attempt to make the last shot count. Usually resulting in that “unexplained flyer”

 

[nagantguy]

1/10 DPMS barrel.
Since my 1.5 inch occurrence I’ve changed some things- PSA trigger- the 3.5 .
New scope mount - went with a Vortex.
So before work this morning took the rifle back out, it’s 3rd range trip.
load was 44.4 varget- over 168 grain Nosler match HP’s cci large rifle primer in lake city brass. A pet load that’s shot well in several rifles I’ve played with. Didn’t have a whole lot of time and it was drizzling rain. Almost no wind. Used the lead sled to take my errors out as much as possible
didn’t fire many rounds- 2 100 yard groups one at exactly an inch for 3 shots. The other at just shy of 1.5 inches with the second of 3 rounds just high of where I thought it should be, didn’t call a flier, didn’t think I’d pulled it .
one three round group at 200- 2.2 inch group again second round a bit of a flier.
One 300 yard 4 shot group. My last 4 rounds The rain was picking up and so was the wind-
This 4 round group was just shy of 4 inches again with second shot being high from the others, so even with this second round flier I seem to have going on seems like about an moa rifle which is more than I expected hafejd30, lots of good feed back in your post thank you- the first trips to the range 100-200 and 300 were shot on different days one trip 200 and 300 hundred shot on same day. With various loads that have given me luck before with other rifles. The milspec trigger was one of the worst I’d ever used. 8 years in the Marine Corps taught me to use a milspec trigger fairly well but this was terrible. This morning no one else was at the range- only can go out to 100 at home- it wasn’t hot with high humidity and I applied all my fundamentals as best I could for each shot with no rush .
I had better groups before with the 165 Nosler ballistic tips and 45 grains Varget it seems. Spent the last several yes in the pistol game and being an instructor at a local academy and am really just getting back into the rifle other than for hunting . So I’m very pleased with these initial groups for a knock around - deer pig coyote plinker.