88 TMK Loading Thread

[kopmantrey]

I shot 4 88tmk loads from a 20" 22 creed rechambered tikka 22-250. This barrel seems to show pressure signs sooner than others I've been around. I copied and pasted my notes below. All loads need backed off slightly for this barrel.

40.5 n160 heavy bolt 3113avg (left 4 shots)
43gn h1000 slightly heavy bolt 3078 avg
36gn h4350 slightly heavy bolt 2947 avg
42.5gn magpro slightly heavy bolt 2933 avg

 

[43.6N]

What’s a 223 WY?

223 Wylde chamber.

 

[Bluumoon]

I shot a bunch of 46.3gr Staball HD today.

Goal was 2775fps.

22creed.

View attachment 1036985View attachment 1036987

It drops from my Harrels so much smoother than H1000.

I think that barrel is broken. The .223 guys are getting almost the same speeds.

 

[Schmo]

I think that barrel is broken. The .223 guys are getting almost the same speeds.

Yeah, seems like he’s had a real struggle on that barrel

 

[43.6N]

I think that barrel is broken. The .223 guys are getting almost the same speeds.

@Nine Banger are you sure your Garmin chrono is reading accurately? Does it need a software update?
I’m interested when you start shooting these at distance, if you start trending high with impacts.

 

[ChrisAU]

It wasn’t hard to get 88 ELD-Ms to near 3000 with my 16.5” 22CMs. So yeah something odd there.

 

[1000yards]

@Nine Banger are you sure your Garmin chrono is reading accurately? Does it need a software update?
I’m interested when you start shooting these at distance, if you start trending high with impacts.

Is this a known issue with Garmins? I did a search but couldn't find anything.

 

[43.6N]

Is this a known issue with Garmins? I did a search but couldn't find anything.

Not a “Known issue”
I’m just curious why his barrel is 250fps slower than other 22cm barrels with similar powders and charges.

 

[mtnbound]

Not a “Known issue”
I’m just curious why his barrel is 250fps slower than other 22cm barrels with similar powders and charges.

He has mentioned before that he is downloading to better match quick drop.

 

[43.6N]

He has mentioned before that he is downloading to better match quick drop.

He’s shooting the same powder at the same charges as the rest of us.
For 22cm on this thread:
My 16” barrel with 43.5gr H1000 was 2930’s.
His 18” barrel with 43.0gr was 2718.

Something doesnt add up.
He’s getting great accuracy, and hitting the target velocity he wanted.
But I have no way of explaining mechanically why his gun is so much slower then we would expect.
That’s all.