I need a little help.

[redandwhite72]

I bought a new browning a bolt in 300 rum here this spring. I also got a new vortex viper scope to ho with it. When I got it I did the shoot clean shoot clean for the first 10 then clean every other for the second 10. And used barnes factory loads. Well I had extremely bad extractor marks on the casings
So I sent the casing back to Barnes and talked to browning. They said to send it to them to check over. Well it took them over 3 weeks to even get it in the system. After that a couple of days and it said ready for shipment. Well they won't tell you what or if they did anything to it. I think they checked the head space and sent it back. Anyway, while trying to sight it in over the summer I didn't have very good luck. Looking on the internet I saw that 300 rums get hot fast and accuracy drops quick. So I wait till it cools off. A few weeks ago I decided to clean it as good as I know how to. Well I noticed the barrel is really pretty rough. It has scratches that run straight with the barrel and not twist with the rifling. I tried to zero in at 300 yards last weekend. Temp around 50. Shot 3 rounds, 4" group 6"-8" low. So I came up 8 clicks. Shot 3 had 1 flyer so I shot 1 more. Had a 3" group 1.5" low. Between groups I walked the 300 yards to check and so the barrel could cool. Walked twice after the second group (forgot to take a pen). So went up 2 more clicks. Should have out me dead on. Shot 3 more and they are nowhere to be found on my 12"x12" target. I cleaned it real good and going to try again tonight. Do you think its getting to much build up after 6-8 shots that its shooting flyers. If so would you try tubbs or would you take it back and trade for a Remington 700. I've shot less than 100 rounds through it. Sorry for the long post. Thanks for any help. Oh yeah, I was shooting hand loads last weekend. 89 grain retumbo, Barnes brass, cci mag primer 180 grain Barnes ttsx bullet seated to 3.600 oal. And I weigh every loads powder so they should all shoot fairly close to the same.

 

[Sully2]

Its not the caliber....but there is something hokey with the scope and or mount.

 

[redandwhite72]

I wondered about the scope too. I thought id shoot it tonight where its at and if its still out of wack with the first shots. If it is I'll turn it back down the 2 clicks I went up and see what happens.

 

[roninflag]

the answer most questions on this forum is -remington sender0 and a leup 6.5-20.

 

[AZShooter]

I feel your pain. Not much fun trying to figure out what changed. There is a checklist you should go through. I swear sometimes we all forget one or more so if I don't mention a few, guys please add to it.

I have no idea of your knowledge so just typing down things to consider. Might be good for others to read in future.

You didn't mention your cleaning proceedure. Maybe you have a copper buildup?


Action screws tight after a range session I have found they can loosen up especially after a recent disassembly which Browning might have done.

scope bases and rings tight
scope ring caps tight
Crown in good condition
bolt face clean


Did you take it apart after Browning returned it? Not a bad idea to look for anomolies. Sometimes stuff can get into spaces like the recoil lug area.

Is there a blind hole for either action screw? If so inspect to be certain no material is in bottom of hole which will give you a false tightness

Is the front scope ring base machine screw contacting the threads of the barrel? This will give another false tightness.

Can you test the scope on a sound rifle?

IMO no need to use the Tubbs treatment.

Please report back anything you discovered.

 

[redandwhite72]

I did a little shooting tonight. I wonder if I some how messed up that batch of ammo. It was shooting good side to side but up and down, it was all over the place with my hand loads. Shots 9-12 were factory Barnes loads. I got a 2.5" group with them at 300 yards. The only problem with them was they were 8" to high. I shot first leaving the scope alone. Then turned it down 2 clicks that I had went up. Which didn't change anything really. I think I'm going to go back down the other 6 clicks then get some more factory loads. I'm going elk hunting in Colorado next week. So I just need something to get me through that then I can jack around with it when I get back.
I got to thinking about when I was shooting Sunday. The shots that were grouping good were nickel plated federal casing that I weighed every powder charge on the balance scale. I'm thinking now, when it started shooting goofy was when I ran out of them and shot the Barnes brass and the powder was weighed on a digital scale. Do you think there is that much difference in the casings or do you think there could be that much difference in the powder using the digital scale. Its a rcbs scale but its not a high $ one.
Azshooter- will check over all that stuff and let you know if I find anything.

 

[RT2506]

There is your problem. You can not change ANYTHING in a load and expect it to shoot to the same place. Yes cases make a difference. You can't sight a rifle in using 2 or 3 different types of ammo. Get ONE batch of ammo either the same factory or the EXACT same load loaded with the same equipment and then go sight in your rifle.

 

[redandwhite72]

Rt2506 thanks for the info. That's kind of what I figured. Do you know why or what makes casings that much different.

 

[AZShooter]

Sounds like you introduced one or up to three variables which altered your results.

Cases: nickel plated brass has different elasticity than naked brass. Wall thickness varies with different manufacturers which changes internal capacity. The same amount of powder in smaller internal space will raise pressure and velocity.

Finally, though I doubt it, the balance could be weighing differently than the elec scale.

Now that have zeroed in on the problem deal with it after the hunt. I'd grab that factory ammo, sight in and go hunt an elk!