Sierra 88 TMK Load Data

[mtnbound]

Copycat haha. I think we found the perfect 223/88 TMK load.

I admit it, I copied you and yes Lever/88TMK is a great combination. I do want to test it during the summer and see how it does with warmer weather.

 

[43.6N]

You’re a 7twist though, you are likley good at all DA’s

7.5 twist here.
Same velocity.
2000ft da on day of testing.
I took it out to 1120yds.
G7 bc held up.

 

[KyleR1985]

I admit it, I copied you and yes Lever/88TMK is a great combination. I do want to test it during the summer and see how it does with warmer weather.

I think you’ll be just fine with 25gr and that COAL, depending on brass capacity.

I was happy with 26-26.5gr in LC brass.

 

[KY_coop]

If i can get these speeds in my 16" 22 arc ill be one happy fella. Just need a stock to come in!!

 

[mtnbound]

Awesome work. Sorry if I missed it, but what DA are you all, and have you tested this at distance?

DA today was 2000. I could only see the 550y target today due to clouds so that’s as far as I shot with the 88/Lever load and it was on at that distance but I need to do some more testing.

 

[mtnbound]

I think you’ll be just fine with 25gr and that COAL, depending on brass capacity.

I was happy with 26-26.5gr in LC brass.

Thanks for the info.

 

[mtnbound]

No kidding. Two good marksman as well, no doubt.

I need to read this entire thread more carefully to look for other loads.

Any recommendations for a powder for a .22-250 with the 88’s? I have a bunch of the traditional H380 from my old 1:12” twist rifle.

Edit - I just ordered some Leverevolution and more H4831sc. Along with some more CCI primers. It's going to be a long, fun summer.

My 22CM and N555 worked the best out of everything I tested.

 

[KyleR1985]

16.5” 223ai howa mini

223ai 3x Formed LC, 88tmk, 27gr lever, cci450, 2.5” oal, .100” off lands:

3 shots averaged 2815fps.



100 yards

 

[NWBLKTAIL]

Well I loaded 5 rounds each of Varget
23.5gr (2640) per Garmin
24gr avg (2700) per Garmin
1x Starline
CCI 450’s
About .015-.020 off touch.

I was shooting at 485ft, but my DA with variables Input through NOAA was -800



No pressure signs at either charge.


Left is 23.5 varget
Right is 24gr.
1/2” dots for reference




Calculated DA via NOAA.

It’s a stormy day on the coast, southerly winds.

 

[FB Trout]

Well I loaded 5 rounds each of Varget
23.5gr (2640) per Garmin
24gr avg (2700) per Garmin
1x Starline
CCI 450’s
About .015-.020 off touch.

I was shooting at 485ft, but my DA with variables Input through NOAA was -800



No pressure signs at either charge.

View attachment 1052278
Left is 23.5 varget
Right is 24gr.
1/2” dots for reference


View attachment 1052280

Calculated DA via NOAA.

It’s a stormy day on the coast, southerly winds.

They appear to be stable at 100 yards with the 8 twist. That is very good info, thank you.

 

[NWBLKTAIL]

They appear to be stable at 100 yards with the 8 twist. That is very good info, thank you.

I’ll know the real story once I get a chance to stretch them out

 

[bigunit]

Just got back from the range after a quick ladder test with the 20" 22-250 ai. Excellent results with n555. Got up to 3160 before getting some pressure signs. Ill back it off to about 3100 where there was a very flat velocity node. Retumbo did ok but not as well for velocity or accuracy. Ill load up a bunch and continue testing. Only jumping about .010"

 

[Scooby-93]

My 22CM and N555 worked the best out of everything I tested.

What speed didn’t it get with the 88 & n555? Barrel length and twist

 

[Scooby-93]

Just got back from the range after a quick ladder test with the 20" 22-250 ai. Excellent results with n555. Got up to 3160 before getting some pressure signs. I’ll back it off to about 3100 where there was a very flat velocity node. Retumbo did ok but not as well for velocity or accuracy. I’ll load up a bunch and continue testing. Only jumping about .010"

Charge weights?

 

[Hill Difficulty]

Update on load dev for 223 Rem, H4895, 450 primers, Lapua brass:

Shot 5 new charges tonight. Got to 2,723 fps with 23.9 grains, ended at 2,769 with 24.3 grains. All same POI and no pressure signs. Seating .035" off (2.51"OAL). I have 2 of the older gen MDT poly mags that fit up to 2.55" OAL.

Pleased at 2,700 fps+ w/excellent accuracy. Seems I'll get to 2,800 fps with 24.5 grains. Might start to sense a little powder crunch at 24.5 so no interest to go faster.

***EDIT to note that the charges I'm reporting are overpressure.***

 

[Gstew1930]

Update on load dev for 223 Rem, H4895, 450 primers, Lapua brass:

Shot 5 new charges tonight. Got to 2,723 fps with 23.9 grains, ended at 2,769 with 24.3 grains. All same POI and no pressure signs. Seating .035" off (2.51"OAL). I have 2 of the older gen MDT poly mags that fit up to 2.55" OAL.

Pleased at 2,700 fps+ w/excellent accuracy. Seems I'll get to 2,800 fps with 24.5 grains. Might be crunching powder at 24.5 so no interest to go faster.

Whats your barrel length?

 

[Hill Difficulty]

Whats your barrel length?

17" w 1:7 twist

 

[Gstew1930]

17" w 1:7 twist

Damn thats quick

 

[bigunit]

Charge weights?

Up to 41 with n555 and 43 with retumbo

 

[Hill Difficulty]

Damn thats quick

For sure.

When my order of 88s arrived I had immediate buyer’s remorse thinking the deep bullet length would use up too much case capacity and end up in the 2,500 fps ballpark.

***EDIT to note that the charges I'm reporting are over pressure.***