Range disappointment after shooting reloads

[Bearcatrp]

Figure this goes in this section. Went to the range yesterday to test out 6 different powders reloads. 308 AR with 16 inch barrel. Everything was going fine until 2/3rds the way through. All of a sudden my shots were going all over the place. WTF. I stop, check to insure the scope didn't come lose. Nope. I always bring factory A-Max rounds as I want to mimic this round. This round is always shoots great. So after about 50 rounds of my reloads, and verifying my scope didn't come lose, I broke out the commercial stuff to see WTF was going on. Shoot, make adjustment on scope, shoot again to see the round went another direction. I burned through 3 boxes of commercial hornady ammo fishing to re zero. I gave up. Range master said barrel heat up. Barrel was a little hot but didn't seem real hot. Always stopped after 5 rounds to inspect the brass and write down my notes. So, to you pro's, will a heated up barrel cause this to the point of not able to zero? Was shooting 100 yards.

[Erud]

Depends what you mean by "all over the place". How was it shooting previously, and what did it change to? A hot barrel can change POI, particularly with lighter barrels, but if it went from 1" groups to 5" groups or something like that, I would definitely say you have some other problem. Are you saying that the factory load also shot bad?

[Bessy]

Typically with a barrel overheating I will see "stringing" What that means is that the rounds start stringing out, this usually happens in a vertical direction, but not always.

The fact you swapped to commercial loads and everything was still hosed indicates that it's the gun not the ammo. Give us a little more info.

1. what profile is your barrel?
2. What make is your ar,
3. What make is your scope.
4. Define "all over the place"? Was it vertical stringing, huge groups


While it could be heat related it could also be related to something inside your scope busting loose.

[JJ]

I would be checking the gas block, barrel nut, anything that could be affecting/touching the barrel.

Second, I would check the scope mounting. Make sure your rings are not resting on the radii leading to the saddle, objective etc. (rings should be about 1/8" away from any radius on the optic body).

Lastly, don't chase individual shots with scope adjustments. Make three shot groups and make inputs based on the results from those sub-groups. Otherwise you could be chasing a shifting POI, with a shifting POA, which will double excaberate your results.

[Bearcatrp]

I would be checking the gas block, barrel nut, anything that could be affecting/touching the barrel.

Second, I would check the scope mounting. Make sure your rings are not resting on the radii leading to the saddle, objective etc. (rings should be about 1/8" away from any radius on the optic body).

Lastly, don't chase individual shots with scope adjustments. Make three shot groups and make inputs based on the results from those sub-groups. Otherwise you could be chasing a shifting POI, with a shifting POA, which will double excaberate your results.

I did exactly this. I started chasing the shots. I always shoot the commercial rounds 1st to get comfortable shooting and insure I am on target. Always shoot 5, same as reloads. Then I begin with lowest and work up. Was on my 4th groupd of reloads with different powder. Thats when things went to ****. 1st, the shots were going right. Thought I was pulling. After a few more that went left, I adjusted. Then the rounds went high. Adjusted. Then went low. All withing 5 inches of center target. Then I stopped on the reloads and started with the hornady 168 A-max's, which all my reloads were with A-max bullets and commercial brass, not LC that I use on my plinking 150 fmj bullets. Did the same thing. Chased the holes until I went through 3 boxes. Stopped! Once I figure this out, have to go re-zero with commercial rounds again.
Here is what I have:
DPMS Oracle 7.62 with 16 inch barrel.
Nikon M-308 scope with nikoplex reticle
Timney trigger
Brass was once fired commercial winchester and hornady brass. NO crimping on these reloads.
Bullets were Hornady 168 gr A-Max
Primers were CCI
Barrel was resting on sand bags
Temp was 70F with little to no wind
Del tone range in st cloud ( just 2 at the range so plenty of room)

[JJ]

I would be checking the gas block, barrel nut, anything that could be affecting/touching the barrel.

Second, I would check the scope mounting. Make sure your rings are not resting on the radii leading to the saddle, objective etc. (rings should be about 1/8" away from any radius on the optic body).

Lastly, don't chase individual shots with scope adjustments. Make three shot groups and make inputs based on the results from those sub-groups. Otherwise you could be chasing a shifting POI, with a shifting POA, which will double excaberate your results.

I did exactly this. I started chasing the shots. I always shoot the commercial rounds 1st to get comfortable shooting and insure I am on target. Always shoot 5, same as reloads. Then I begin with lowest and work up. Was on my 4th groupd of reloads with different powder. Thats when things went to ****. 1st, the shots were going right. Thought I was pulling. After a few more that went left, I adjusted. Then the rounds went high. Adjusted. Then went low. All withing 5 inches of center target. Then I stopped on the reloads and started with the hornady 168 A-max's, which all my reloads were with A-max bullets and commercial brass, not LC that I use on my plinking 150 fmj bullets. Did the same thing. Chased the holes until I went through 3 boxes. Stopped! Once I figure this out, have to go re-zero with commercial rounds again.
Here is what I have:
DPMS Oracle 7.62 with 16 inch barrel.
Nikon M-308 scope with nikoplex reticle
Timney trigger
Brass was once fired commercial winchester and hornady brass. NO crimping on these reloads.
Bullets were Hornady 168 gr A-Max
Primers were CCI
Barrel was resting on sand bags
Temp was 70F with little to no wind
Del tone range in st cloud ( just 2 at the range so plenty of room)

Tell me that you mean the forearm was resting on sandbags. Even then, you need to consider the fact that your barrel is not free floating, so pressure on the forearm can give you issues, much less if you were actually resting directly on barrel.

And don't chase shots. The problem you have, is you do not know if its a gun, ammo, or optic issue. You haven't established a baseline of accuracy for any of the above since the erratic results have begun.

[Bearcatrp]

I have a folding hand grip up front. That was resting on the sand bags (folded). I was zero'd before I began shooting the reloads verified with the commercial rounds. I made the mistake of chasing the rounds. I could possibly see barrel heat possibly doing this after a few hundred rounds but heck, around 70 when it started. Plus I stopped after every 5 shots to write my notes and inspect the brass. Just cleaned it this morning. Everything seems nice and tight.

[farmerj]

can / did you keep your targets?

posting them would be a real help.

Did the wind pick up?

[Bearcatrp]

can / did you keep your targets?
posting them would be a real help.
Did the wind pick up?

Unfortunately no. Was so pissed I forgot to remove them. Wind did not pick up. I plan on reloading same batch again and trying again. If it happens again, will find someone who is well versed in AR10's that has the tools to check it out properly.
I did find out I like varget better than 4064 and did get to test that group before things went to hell. Wondering if I should skip buying a few boxes to compare and just reload what I think would work well. Scope is out of adjustment due to fishing but might be cheaper. What do you guys think? Get some hornady and re-zero then continue on my reloads or just go for it with the varget?

[farmerj]

have someone video tape yourself too.

[OldmanFCSA]

Scope failure.

[Bearcatrp]

Scope failure.

That did cross my mind. So, is there a test of some kind to determine it actually failed before contacting nikon and sending it in? Being on a AR with less recoil than a bolt, and the M-308 is designed for the AR 308 platform, would think this scope would be tough enough not to fail. BTW, you didn't answer my PM's.

[farmerj]

Scope failure.

That did cross my mind. So, is there a test of some kind to determine it actually failed before contacting nikon and sending it in? Being on a AR with less recoil than a bolt, and the M-308 is designed for the AR 308 platform, would think this scope would be tough enough not to fail. BTW, you didn't answer my PM's.

Basic box pattern.


Up 10, right 10, down 10, left 10. (Or any variation)


You should be back where you began. Shoot 3 shot group after every adjust.

[bman940]

Agree, the barrel resting on anything that can cause pressure could be a big problem. You have a very stout rifle from DPMS. I did some product testing 4 years ago with the oracle in 7.62 and 5.56. 1000 rounds out of each in an afternoon. I got the barrel so hot on the 7.62 when I set it next to a range bag it melted vinyl onto the barrel. I never had accuarcy less then 1.75 inches throughout all the testing.
I once had an upper that could barely manage minute of pie plate so I sent it back to the manufacturer, they said barrel nut was loose, sent it back, no better so I returned it.

Doing a box test is great, moving to 50 yard might be easier att his stage too. Check out Spot On so that you know where you need your POI to be for a 100 yard zero.

A pic of what you have now would be great, show target as well.

Definitely get the pressure off the barrel while shooting.Here's a pic of Oracle I was testing, notice where I have the front rest.

[Bearcatrp]

Ah crap. I did have the barrel, not the hand guard, resting on the sand bags. So when doing the box test, I keep cross hairs on one point all the time while making adjustments and shooting to mimic a box (4 holes in 4 corners)?