Accuracy Change?

[Timberelk]

You need a BH 209 specific plug.

The plug I am using now is the same design as the original plug I was using when I had good accuracy. It’s the OE plug that accepts a 209 primer

 

[X-ring]

The plug I am using now is the same design as the original plug I was using when I had good accuracy. It’s the OE plug that accepts a 209 primer

Your groups are strung horizontally. Have you taken into account wind deflection? Many people assume that the wind won't move a bullet at 200 yds. X

 

[Timberelk]

Your groups are strung horizontally. Have you taken into account wind deflection? Many people assume that the wind won't move a bullet at 200 yds. X

Thanks for calling that out. While there is usually some wind 5-8mph when shooting, to string it that much at 200 yards wouldn’t I need to be shooting into a changing head wind that is 30mph+? Haven’t seen this issue in the past years

For that target there was some (5-8mph) head wind for the yellow group, red group had little to no wind

 

[X-ring]

Thanks for calling that out. While there is usually some wind 5-8mph when shooting, to string it that much at 200 yards wouldn’t I need to be shooting into a changing head wind that is 30mph+? Haven’t seen this issue in the past years

For that target there was some (5-8mph) head wind for the yellow group, red group had little to no wind

A 10 MPH wind will drift it that much. Some of the guys here that have ballistic programs will be able to help you estimate wind deflection if you give them some basic data on your load/bullet combination. X

 

[Timberelk]

A 10 MPH wind will drift it that much. Some of the guys here that have ballistic programs will be able to help you estimate wind deflection if you give them some basic data on your load/bullet combination. X

Thank you for trying helping me figure this out but I don’t think the wind is the issue at hand. If it was, my grouping last night with no wind would have been great but it was horrible at 7+ inches

I ran a few ballistic scenarios with and without a 10mph head wind. The difference is .12 MOA which comes out to approx .24 inches at 200 yards.

Plan on changing the scope today and trying to shoot again this evening

 

[ElDiablo]

The plug I am using now is the same design as the original plug I was using when I had good accuracy. It’s the OE plug that accepts a 209 primer

The OEM TC plugs work great with Bh209. No such thing as a Bh209 specific TC plug. (That’s a CVA issue).

 

[ElDiablo]

You might check the recoil lugs to make sure they’re not loose.

 

[Timberelk]

You might check the recoil lugs to make sure they’re not loose.

Just checked them a no dice, they’re both tight to the barrel. Thanks for the suggestion though!

 

[Shorty]

When changing out ur scope, check the base mount screws, they might have loosened. Its not uncommon in heavy recoil guns…good luck..

 

[BigBoresmokepole]

When changing out ur scope, check the base mount screws, they might have loosened. Its not uncommon in heavy recoil guns…good luck..

Also when changing out scope bed the mounts and locktite all threads. I run Leopold scopes on all my rifles they do fail at times. Muzzleloaders can recoil pulse the scopes if shooting large loads of powder and heavy bullets

 

[LHR]

I can tell you if you’re getting more blow by than normal with BH209, this could very well be your issue.
What primers have you tried since changing the breech plug?

I’m guessing the other plug fit your primers better than this one does?

Are you shooting the same primers as before the accuracy trouble?

Get that sorted and I’d bet your groups improve greatly.

I had the same thing happen with my daughters rifle, switched to a cheddite primer (wider than most) and the blow by problem went away and groups tightened right up again.

 

[Kevin C.]

The plug I am using now is the same design as the original plug I was using when I had good accuracy. It’s the OE plug that accepts a 209 primer

I’m trying to help. I shoot 3 shot cloverleaf accuracy, so I’m not steering you wrong. BH 209 requires a larger flame hole, hence their proprietary breech plugs. If you weren’t using one before, you honestly need to be. Blackthorn will tell you as much.
Is this the answer to your issues, maybe not. But I’ve had several CVA rifles and pistols, and first thing I do is order a 209 breech plug. Every one of my black powder rifles, all CVAs, have had zero issues and sub1/2 inch accuracy.
I shoot 100 grains with a 250 grain Spitfire TMZ Bullet.
Just ordered a muzzle brake and bought some Hornady 340 grain ELD bullets.
We will see how that goes.

 

[Timberelk]

Alright I think we’re making some progress, thanks all.

Took the Nikon off, checked the base screws and they were tight, installed the leupold. Took me 4 shots to get fairly sighted in and then these were the next 3 shots at 100 yrds. Each square is 1”. This is the kind of accuracy I’m used to seeing.

Will follow back up with 200 yard groups

 

[GM54-120]

I’m trying to help. I shoot 3 shot cloverleaf accuracy, so I’m not steering you wrong. BH 209 requires a larger flame hole, hence their proprietary breech plugs

Just a FYI, The Omega plug and the MLII plug were both used for initial testing of BH209 before its release. The Omega plug is is probably better than most at igniting BH209. Why do you think the powder side was copied by that "other brand"?

BH209 ignited just fine with a .032" flash hole. Anyone that thinks you need anything larger simply has not used a good breech plug.

 

[BigBoresmokepole]

It will open up a little a 200yrds and you will have to maybe up the charge a little just make sure it groups before making scope adjustments. I believe your last scope was the problem

 

[Timberelk]

Wanted to follow up in case this helps anyone in the future.

First, thank you to all that helped me figure this out. I was reluctant to pull the Nikon scope but glad I eventually listened. Once again this community got me on track to an accurate muzzleloder


200yards:
Shot 1: clean barrel (shot two primers before loading, this is what I do to get the barrel a little dirty)
Shot 2: 8 minute wait to let bare cool
Shot 3: 10 minute wait. I moved the scope to the left 3 clicks which is approx 1.5” at 200 yards. All I can think is I made a bad shot. I think it was the connection between my shoulder and the butt pad, it was on a different spot of my shoulder than the other shots.
Shot 4: 3 minute wait. Right where it should be, approx 1.5” the the left of the first two shots


Shot 3 bugged me a bit but even if I counted it into my group size, my group after moving the scope is approx 4”. Not horrible for 200 yards. Without it, I’m shooting sub MOA groups. If I was planning on shooting further than 200 yards I’d look more into it but with how fast the bullets drop inches and ft lbs of energy past 200 yards, I’m just not interested in hunting beyond that distance

Thanks again all!

 

[BigBoresmokepole]

You will need a pointer bulletif you want moa. xtp from my gun at 200yrds on my best day 1.5 and at max load. I'm glad it's feels like it is grouping for you nothing like confidence in your gun. 200 is the max for me and xtp bullets.

 

[LHR]

You will need a pointer bulletif you want moa. xtp from my gun at 200yrds on my best day 1.5 and at max load. I'm glad it's feels like it is grouping for you nothing like confidence in your gun. 200 is the max for me and xtp bullets.

I used to shoot xtp's and still do, but not for longer ranges due to low BC. I had been shooting xtp's at 200 yards one day and had a two inch five shot group. Then I moved out to 300 yards, shooting at a 13" steel target, I couldn't hit it more that 1 out of 4 or 5 shots.

I think the bullet was just subsonic at that distance and was wobbling all over the place.
Shooting the exact same load, only with an SST, I was shooting 300 gr. bullets in both, now I could easily hit the gong at 300 yards every shot. Only difference was the higher BC bullet.

Only problem was that the performance of the SST was not what I wanted, they don't seem to open up at all, but penciled right thru on my elk that I shot later that year. Then went on to the Harvester White Lightning, and got the performance I was after.

 

[bronko220002]

I replace mine at 0.036".

Problem is you can't find Encore/Omega breech plugs anywhere. I've looked. I'll be modifying mine with vent liners when they wear out.

 

[jsteurrys]

Problem is you can't find Encore/Omega breech plugs anywhere. I've looked. I'll be modifying mine with vent liners when they wear out.

Switch to a bushing and it will last way longer unless you shot a lot.