Browning Muzzle Threading Woes

[odie73415]

I would bet on it is the harmonics .
I have been using cans exclusively for14yrs on all my rifles.
Never had an issue untill a sedero conture in 22 ppc on a trued bedded Rem 700.
Without the can high 1's to low 2's on average.for 5 shot groups. With the can it would oped up to 1 to 3 in.
Worked on load,different bedding styles and compounds all the gambit. That gun would not/ will not shoot with a can on it.

 

[pavementends]

I have had both good and bad experiences with "gunsmiths" and have learned to have non critical work done first. I would talk to the smith who did the work. He will either offer to check the work for you or insist that he has never had an issue. Sounds like your barrel is long enough to re-do if needed. With a stock that is not bedded hanging a pound on the end of the barrel can cause issues. Since it shoots as before without the can the crown is probably ok although the threads may not be concentric. Good luck.

 

[JAYgs8163]

Is the barrel not floated and making contact with the stock? 1) If it isn't floated I would bet that hanging your can on the end is causing more contact and interference to the stock and creating your POI issue. 2) If it is floated, but has very close clearance between the barrel and stock, the additional weight of the can could be causing the barrel to whip more and make contact with the stock upon firing thus causing your POI issue. How long is the barrel? After checking threads cut correctly the first thing I would do is bed the action and float the barrel with reasonably good clearance. Keep us updated as very curious how this pans out.

Have someone stand to the side, record a firing sequence without the can and with the can and watch back in SM and look for increased whip.

 

[waspocrew]

Seems like the next thing to do is to get an alignment rod to see if your threads are concentric.

 

[VenatusDominus]

Seeking wisdom. I had the muzzle threaded on my Browning Sako 22-250 and took it out and it seems to be unhappy shooting with my cans. It goes from easy sub-moa with nothing on the barrel (just as it was before) to wild 2-3-4 inch groups at 100yds. Same experience with 3 different cans, including a TB Ultra 9, ranging from 22 cal to 30 cal. I use my cans across multiple hosts and this is the first time I have had an accuracy problem. (4 years of shooting with cans.) First reaction was dirty cans (my rimfire can causes significant accuracy problems on my guns once it gets dirty.) So, I spent a week cleaning all of my centerfire cans. Back to range. No luck. Hmmm, well only other trick was to redo load development. So, ran H380 ladders with 3 bullets and no luck. Same thing. Crap with can on and no trouble with can off.

I want to start with the assumption the gunsmith did it right. He did other work for me and it was well done. I am running through 22 cal cans and 30 cal cans. Same problem.

So the fact that it shoots well when I pull the can off suggests I don't have other problems. To me it is amazing how bad this gets. Not sure where to look or what to check. Any suggestions?

ps - if people are interested, I would be happy to post a write up on my can cleaning exercise - it was enlightening.

I have a 300 Weatherby Mark V synthetic stock with a slim 24" barrel I purchased new in 1991. In Dec 2020 I sent it to the factory to have the muzzle threaded for a brake (total cost with shipping was $241.92, that included the factory brake and a screw-on thread cover for use when the brake is off the gun). The slim barrel required 1/2x28 threads. I had to purchase the factory radial brake to not void the factory accuracy warranty. As soon as I received the rifle back from the factory, I swapped the factory brake with the PA Hypertap below. The Weatherby break is rated at 54% recoil reduction and the PA Hypertap is rated at 84% recoil reduction.

1 x Precision Armament HYPERTAP Muzzle Brake Slim 7.62mm/.308Cal, 1/2-28, Black, 7.62mm/.308, A04614

I spent 6 months working up hand loads for the gun and could never get it to group less than 1.5" at 100 yards with the Hypertap. The felt recoil reduction was in the range they claimed at 84%. I put the factory brake back on and the felt recoil was greater, but about what Weatherby claimed at 54%. Yeah, the radial brake is not ideal when shooting prone, but with the factory brake the gun regularly shoots 0.3" groups at 100 yards, providing I do my part. The Hypertap brake is definitely better at mitigating recoil, but, I think the size/weight of the Hypertap was just too much mass at the end of a very slim barrel, causing it to amplify barrel harmonics and whip about, adversely affecting accuracy. I was planning to add a can to this gun when I move out of California, but after this experience I don't think it will work.

 

[C-130 Dude]

Thanks. Yes, very crappy. It is medium contour. No indication of baffle strikes. Besides, I would think at 22-250 velocity, baffle strikes would vaporize bullets. Maybe not. We certainly were worried about that and the misalignment and hoped moving up to 30 cal cans would solve the problem. It did not.

If there are no baffle strikes, I'd say you may need to start over working up different powder type/weights. It's a hassle, but if this happens using different cans (with no evidence of baffle strikes), what else could it be?

 

[Horse1]

Those Browning/Sako's with their multiple step-down barrel contours can be a pain in the rump. There's more places for things to get wonky.

 

[R. Cram]

I put a break on my buddy's rifle, a weatherby, and the barrel was tight enough on the reciever I didn't want to risk breaking something to unscrew it so I chucked up the reciever in the 4 jaw and dialed the OD of the barrel at the breach, then put a live center in the muzzle and in the center of the barrel we had .070 run out, it was amazing to see so at that point we didn't know if the barrel had been bent or if the bore was that far out of center with the OD and he was a horseback hunter so I went with the bent barrel and we pushed the center of the barrel back with the steady rest and cut threads on the muzzle end and put on the break and when we shot it the zero was way off and we had copper wash in the break so we bored out the break and got rid of the problem with the bullet hitting the break and the rifle shot as well as before but a break is only 2 inches or so long where a suppressor is 6 or so I would not put on a suppressor without using range rods and dialing in the end of the barrel. I set back a barrel 4 inches for a freind a bit ago and it was a top quality barrel and when I cut off the 4 inches off the breach end and recentered the bore and put the live center in the bore the OD was off by .010 so that bore was not straight by .010 in 4 inches.

 

[Taj]

You've probably checked this but make sure the added weight of the can is not pulling the barrel into contact with the stock in the barrel channel.

 

[HuntingBronco]

I have a 300 Weatherby Mark V synthetic stock with a slim 24" barrel I purchased new in 1991. In Dec 2020 I sent it to the factory to have the muzzle threaded for a brake (total cost with shipping was $241.92, that included the factory brake and a screw-on thread cover for use when the brake is off the gun). The slim barrel required 1/2x28 threads. I had to purchase the factory radial brake to not void the factory accuracy warranty. As soon as I received the rifle back from the factory, I swapped the factory brake with the PA Hypertap below. The Weatherby break is rated at 54% recoil reduction and the PA Hypertap is rated at 84% recoil reduction.

1 x Precision Armament HYPERTAP Muzzle Brake Slim 7.62mm/.308Cal, 1/2-28, Black, 7.62mm/.308, A04614

I spent 6 months working up hand loads for the gun and could never get it to group less than 1.5" at 100 yards with the Hypertap. The felt recoil reduction was in the range they claimed at 84%. I put the factory brake back on and the felt recoil was greater, but about what Weatherby claimed at 54%. Yeah, the radial brake is not ideal when shooting prone, but with the factory brake the gun regularly shoots 0.3" groups at 100 yards, providing I do my part. The Hypertap brake is definitely better at mitigating recoil, but, I think the size/weight of the Hypertap was just too much mass at the end of a very slim barrel, causing it to amplify barrel harmonics and whip about, adversely affecting accuracy. I was planning to add a can to this gun when I move out of California, but after this experience I don't think it will work.

View attachment 639500

I sent my WBee Ultralight 30 cal to Thunderbeast to thread the barrel. Even with the whippy barrel, it shoots just fine with the TBAC Ultra9. Yes, this likely shot my warranty. Wbee has taken good care of me, they don't owe me anything.

 

[HuntingBronco]

Thanks everyone for the tips and suggestions.

So I was able to get a 0.2195 pin gauge in the barrel with nearly no wobble. 0.2200 would not fit. Screwed the TBAC brake onto it to see if there was anything glaring. Doesn't look like it to my eye. Not sure this proves anything and doing better requires a longer gauge or possibly putting it in a lathe.

When I discussed the job with the GS, he assured me he was going to center the bore (not the barrel/OD) in the lathe and cut threads and shoulder to be square to the bore. Complicating matters, he left the employ of the shop.

Does this pic tell anyone a better story?

Next step?

Take it back to shop?
Perhaps put a piece of shotgun shell under foreend to put more pressure on barrel? FYI-the barrel is NOT free floated.
Put a piece of shotgun shell under recoil lug to float and see if that helps?

I really don't want to shot 200 rounds through this to find out it's the threads.

 

[FireFlyFishing]

Thanks everyone for the tips and suggestions.

So I was able to get a 0.2195 pin gauge in the barrel with nearly no wobble. 0.2200 would not fit. Screwed the TBAC brake onto it to see if there was anything glaring. Doesn't look like it to my eye. Not sure this proves anything and doing better requires a longer gauge or possibly putting it in a lathe.

When I discussed the job with the GS, he assured me he was going to center the bore (not the barrel/OD) in the lathe and cut threads and shoulder to be square to the bore. Complicating matters, he left the employ of the shop.

Does this pic tell anyone a better story?

Next step?

Take it back to shop?
Perhaps put a piece of shotgun shell under foreend to put more pressure on barrel? FYI-the barrel is NOT free floated.
Put a piece of shotgun shell under recoil lug to float and see if that helps?

I really don't want to shot 200 rounds through this to find out it's the threads.

I'm thinking bedding and free floating the barrel is what's needed.

 

[HuntingBronco]

You've probably checked this but make sure the added weight of the can is not pulling the barrel into contact with the stock in the barrel channel.

The barrel is not floated and makes solid contact with the stock. Reluctant to bed, float or change pressure points as it shoots great without the can. I just don't like shooting without a can. Again, first gun of many not tolerant of the can. (Might be the first one that isn't floated.

 

[JAYgs8163]

Bed the action and float the barrel, or don't and use the can on something else