Anyone have a solution?

[Deeznutzr6]

I wanted to see if anyone can provide me with some insight on were my problem may lie.

I have 2 rifles which are about 2 years old. Both rifles have been great out of the box. I have been able to create .325" inch groups out of each rifle on many occasions. However, both rifles have progressivley started getting worse and worse from a standpoint of accuracy. To the point I am shooting 1.5-2.0" groups. I am using the same loads that I have had success with, the only changes I have made was going from Winchester primers to Federal Match primers. Although initially after the change I still had good groups.

I have tried cleaning it thouroughly (I mean very, very clean) I have also tried cleaning it less between groups. But it has not helped. I wondered if anyone had any inforamtion on where to start.

Also, how many reloads can one case handle. I understand it will vary between cartridge to cartridge, just looking for a ballpark. I wonder if the cases are getting a bit old 8-12 reloads.

I appreciate you assistance and thank you in advance for any response you may have.

Thanks,


Derek

 

[JD338]

Sounds like copper fouling to me. What are you using to clean your bore?
Try some Sweets 7.62 Copper solvent and Shooters Choice MC #7.

Also check to make sure the actions screws are tight as well as scope rings and bases.

JD338

 

[Guy Miner]

Tell us a bit about each rifle.

Round count? Cartridge?

What kind of barrel cleaning are you doing?

Also - have you checked all the bolts/fasteners for tightness? Stock/action? Scope mounts? Rings?

How about your handloads? Have you been trimming the cases?

Just areas to watch...

 

[TScottW99]

All good advice above.

I would work on one problem at a time. Check your mount and rings, then shoot. Clean the copper out, then shoot (I use Barnes CR-10 and am amazed by the amount of copper removed), etc... etc...

 

[Deeznutzr6]

Rifle info:

Browning M-100 Eclipse 7MM WSM
160 GR. Nosler AccuBond 61.5 GR H4350E
200-300 rounds

Browning A-Bolt Stainless Stalker 300 WSM
180 GR. Nosler AccuBond 61 GR VV N550
100-200 rounds

Truth of the matter is I have not been very diligent about trimming the cases, that was one thing I considered as a possible problem. Will MM's make that much of a difference?

My cleaning practices I consider to be above average. I use Sweets 7.62 and Barnes CR-10 religiously. I will clean it until no blue (copper fouling) comes out of the breach. Sometimes it take a few hours.

I will check the mounts. I use quality optics (IOR and Nightforce) and they were professionally mounted so I didn't think that could be a problem. I will check them.

Any other possibilites?

Thanks guys, I appreciate the assitance.

Derek

 

[Guest]

So far, everyone has hit right on with the things to look at. I will add only a couple of thoughts.

First, try one of the foaming bore cleaners, as I have recently become a serious believer in using them, having cleaned a rifle (rather thoroughly) and believed it was clean, I ran some Break Free foaming bore cleaner through it just for a test, and the first patches came out navy blue! Do a search here for my post on this, you might be surprised the number of folks who had similar problems and cleared them up with some foam. Just be sure to oil, and re-oil, the bore afterward, as the foam cleaner is pretty good at getting everything out, including all the oil down in the pores of the metal, so things will begin to oxidize relatively quickly afterward.

Second, have you thought about switching back to your previous primers just to see if it makes a difference? I know you said accuracy fell off later on, but it might be a point of issue. I doubt it, but without having my hands on the rifles, I'm grasping a bit.

Also, how hot do you let the barrel get with these guns while shooting? Throat erosion is a real threat with both, though not as much with the 300, and not really much with either if you aren't shooting a ton at a time, with a really hot barrel. Do you have a gunsmith with access to a borescope? He might be able to tell you if there is erosion. I'm told (by people here) that it will look like dark areas in the throat, or perhaps some cracked looking (dry lakebed) areas if you can see well in the chamber.

Check all the screws is good advice. Even professionally mounted stuff doesn't always hold tight, and a loose mount could create some erratic groupings.

I'm with JD, leaning toward copper in the bores, as both guns are doing the same thing.

One last thing to check, and don't take this personally. Have a friend load it up for you, and put a dummy round in it (no primer, no powder, but a bullet so it will feed). You may find that you have developed a flinch or some form flaw that is feeding your group size.

Good luck, and let us know what you find.

 

[OU812]

Rifle info:

Truth of the matter is I have not been very diligent about trimming the cases, that was one thing I considered as a possible problem. Will MM's make that much of a difference?

Yes trimming or there lack of can make a very big difference in POI and if your measuring in MM that is HUGE when a few thousands makes a difference. I always trim all my brass to .003 above the min. Cases stretch over time and must be trimed to length with in spec for the caliber.

I don't have much more to add to the great advice that has already been given but have you checked your action screws? If they are loose they can cause you issues with POI shifting.

 

[Desert Fox]

I will check the mounts. I use quality optics (IOR and Nightforce) and they were professionally mounted so I didn't think that could be a problem. I will check them.


What do you mean professionally installed? By a gunsmith, or a fellow who works over the counter where you bought your rifle? That being said, I have a feeling that something is loose. Start checking action screws, base and rings screws and see if there's any play before you miss around with your reloads. Action screws, ring bases screws and rings screws, if not torqued properly, can come loose so, if I were you, I'll start there. Good Luck.

 

[kraky]

Hopefully when you say you haven't been diligent about trimming your are still keeping your brass in spec with trimming requirements?

If not that is extremely dangerous and could have a huge effect on accuracy. I have a friend that wasn't watching his trimming and he actually cracked a lug on his bolt due to a high pressure spike.

If you have some at min spec and some at max spec I wouldn't think that would cause much of an accuracy change to a good shooting load that the gun likes.

 

[steve4102]

All great advice above! I would start with the scope and mounts also. Then, because you are having this problem with two separate rifles I would look for a common denominator or denominators. From the info you have given so far there are a few that come to mind.

First, primers, you switched primers and things went to hell, not right away, but went to hell just the same. Go back to the Win primers and see if things improve. Are you using Mag primers?

Second, you are cleaning both rifles with the same product and procedure. You may want to check that out. Are you cleaning from the breach or the muzzle? Is it possible that with your vigorous cleaning you damaged the crowns?

Third, the Shooter, lots of horse power in them WSMs with a fairly light rifle. Could be that you are developing a flinch. Have someone else shoot your rifles.

Fourth, You are using the same scale for both loads, yes. Is it possible that your scale is off and your loads are of different charges than your previous loads?.

Fifth, Your brass length may be out of specs for both cartridges. Trim them after they have been sized.

Sixth, anything else that would affect the accuracy of both rifles.

 

[Deeznutzr6]

Wow a lot of information to respond to, I appreciate it.

I checked the rifles and was able to tighten the rings, bases, mounts and action. They were not real loose but I just cinched them down to reasonably hand tight. I never played with this before, becasue I thought there was specific tourque measurements that my gunsmith adheared to when modifying the triggers and mounting the optics. But we will see if this has an impact.

I have not trimmed my cases in a while, however they are well within the max limit for length, but there is variances between each case.

I went through another cleaning cycle using the usual tecniques and also went and got some bore foam. No copper fouling is coming out so I think that is taken care of. I clean my gun from the bore out to the breach. I use a bore guide and I use nylon brushes. I am very mindul when it comes to protecting the crown, as I know how important it is to the rifles accuraccy. I inspected them thouroughly and they don't looked damaged.

I guess the flinch is a possibility, but I doubt it. while they are powerful cartidges I do not notice the recoil at all. The M-1000 weighs 14 lbs and both have limbsave recoil pads. They do not bother me at all. but I will take that as a possibility and have some else shoot them to eliminate another variable.

I think I answered all questions, and I apprecaite the additional response.

Can anyone tell me how many reloads I can expect out of one case before it starts to become questionable?

Thanks,


Derekl

 

[JD338]

Can anyone tell me how many reloads I can expect out of one case before it starts to become questionable?

Thanks,


Derekl

That can be tough question to answer. Depends on quality of brass, if the load is mild or max, neck size or full length resize, and chamber dimensions. You could get from 2-10 depending on the above factors.

JD338