6mm Creed Scattergun

[PinesAndProjectiles]

I have a Tikka that's been rebarreled by PVA. I am shooting the 105 Hybrids over 40.7 grains of H4350, .020" jump and CCI 450s in 6.5 Peterson SRP brass that has been sized down to 6 Creed. Velocity with this load was 3075.

Because of the .2735 neck, some pieces of brass were tough to chamber.

Thanks to a member here, I was able to neck turn my brass down to .271".

Since neck turning, my 1/2 moa rifle is now 1.25 to 2 moa at 100 yards.

I've shot almost 100 rounds, varying from 40g up to 41.3 grains and nothing will group under an inch.

I've kept everything the same except the brass.

Yesterday, I came home after another bad range session. I removed my rings from the rail, checked torque on the rail. It was good. Ive checked the ring torque, it was good. I removed my can and adapter and ran them through the ultrasonic cleaner thinking maybe the lock up of the can wasn't consistant, but that isn't it. I've checked the action screws and they are good.

I also cleaned my rifle thoroughly, even though I only had 100 rounds on it.

My next step is to remove the chassis from the rifle to see if there is something stuck between the chassis and barrel.

Any other idea on what it could be? Does the neck turned brass need to be fire formed after trimming? The brass was 2x fired when I turned the necks so I would think it would be all good.

Thanks for any help.

 

[Deleted member 113831]

I'm assuming you resized after turning the necks? Some possible causes: the neck needs to be turned until the cutter takes just a small cut from the shoulder below the neck junction. Brass meeds to be resized after turning because the mandrel can cause runout and loss of neck tension. Your neck tension has changed anyway because the necks are now thinner so you may need to rework the load.

 

[PinesAndProjectiles]

I'm assuming you resized after turning the necks? Some possible causes: the neck needs to be turned until the cutter takes just a small cut from the shoulder below the neck junction. Brass meeds to be resized after turning because the mandrel can cause runout and loss of neck tension. Your neck tension has changed anyway because the necks are now thinner so you may need to rework the load.

Thank you. I did not size after turning the necks. I read somewhere that this wasn't needed.
I should have mentioned in the original post that I ave also tried some necked down Prime brass with the same results.

I also bought some Hornady ammo, both the 103 and 108, and they also are terrible. I've tried shooting suppressed and not suppressed with the same results.

 

[PinesAndProjectiles]

Should have mentioned, I have 800 rounds on the barrel so I wouldn't think it's toast quite yet.

Here's photos of the groups at 100 yards.

The smalles one, the far right of the 108s is about 1.25" and they increase from there.

 

[Deleted member 113831]

Hmmm...there may something else going on here besides brass.

In the OP it sounded as if it was just the neck turned load that suddenly stopped shooting. Every gun is different, and 800 rounds doesn't sound excessive, but then again, rate of fire matters. It could go in even less than 800 if it was shot hot fairly often. I'm not saying it was...just another possibility. These smaller caliber barrels don't just fade away like a 308 barrel for instance. When they go it is often dramatic.

I find it odd that it would so neatly coincide with your brass change, but it isn't impossible.

 

[PinesAndProjectiles]

I agree. At first, I thought it was brass. Now I'm leaning towards the barrel, or possibly the scope shit the bed. I put on a different scope that I know works. I'm going to hit the range tomorrow morning and find out. I'd go now but it's snowing and blowing like a banshee out there.

I bought some camera thingy off of the Amazon that I can stick down my barrel. I'll take a peek after dinner but the quality of it sucks so I don't expect to see much.

 

[Rangemaster]

If its the brass, load up some new brass and go fire form.
my 6mm creedmoor necks are .270

 

[PinesAndProjectiles]

I doubt it's the brass or my reloading techniques. I've tried two different brass types in my reloads and two types of factory ammo and they all look like I was shooting an AK with open sights at 1000 yards.

 

[pell1203]

MinnesotaMullisha, since you seem to be running out of ideas... grab your scope and try to wiggle it to confirm/verify your picatinny rail is still securely attached to your rifle's receiver. You are trying to see if the rail lifts or rocks just a tiny bit.

I had a .308 with a QD scope mount that all of a sudden started acting up the way your Tikka is. The problem turned out to be a slightly loosened screw attaching the front of the picatinny rail to the receiver. This introduced enough flex into the system to open up the groups from sub MOA to about 3". Once the loose screw was tightened, and the QD scope mount was reattached to the rail at the same location, the rifle went right back to shooting sub MOA.

Sometimes we overlook the simplest solutions and go looking for harder problems.

EDITED TO ADD: Never mind, just re-read your OP and saw you had re-torqued the rail screws! I'll keep watching for a solution.

 

[PinesAndProjectiles]

Thanks Pell. I mounted up an SWFA 3-15 that is known to work. Today I’ll find out.

I removed the chassis from the BA yesterday and didn’t find anything worthy of noting here.

I also ran my Giraffecam into th barrel but couldn’t see much. I could see better with a flashlight aimed into the bore. I could see the lands and they looked to be about 1/4 inch from the neck from what I could tell. Hard to gauge distance whil looking into the barrel.

 

[CanSniper]

Put a q'tip in barrel and use the camera to push the q'tip in alittle, then pull the camera back a little to veiw the barrel. You will be surprised how much better you will see inside.

 

[Deleted member 113831]

Put a q'tip in barrel and use the camera to push the q'tip in alittle, then pull the camera back a little to veiw the barrel. You will be surprised how much better you will see inside.

That is interesting. I've never heard that tip before. What does the q-tip do to help? Is better focus, or better light?

 

[PinesAndProjectiles]

I was out again this morning after putting a new scope on the rifle. Groups improved considerably, even in the 25+ mph winds.

I’m going to load up a few more rounds and head out tomorrow when the winds settle down.

Thanks for all the advice. I will update the post after the range trip. And @CanSniper, I’ll try the Q tip trick!

 

[PinesAndProjectiles]

Update. Went out today and put up some 3/4 moa groups shooting the same loads as I was before, even with some mirage. Thanks for the help!

 

[pell1203]

So what was the problem? If scope, are you going to mount it and test it again to confirm/isolate issue?

Which scope? ?

 

[PinesAndProjectiles]

The scope doesn't seem to hold zero. I have a match this weekend, but afterwards I'll spend some time trying to determine what is wrong with it. I'll try to get my hands on one the scope tracking bases that are out there and do some testing.

 

[demolitionman]

The scope doesn't seem to hold zero. I have a match this weekend, but afterwards I'll spend some time trying to determine what is wrong with it. I'll try to get my hands on one the scope tracking bases that are out there and do some testing.

Which scope? We like details c'mon man!

 

[PinesAndProjectiles]

Sorry, Gen 1 Bushnell XRS with the G2 reticle