Sierra 88 TMK Load Data

[Schmo]

88 TMK in Tikka 18” 8 twist 223. Approximately .100” FB
Virgin Starline 5.56 brass
CCI 450 primers
25 grs N540 (it’s a little hot)
2.500” COAL
DA was 0 - -500’

 

[Nine Banger]

22 Creedmoor
14.5" BBL
2.680"
46gr N565
2775fps

 

[The Guide]

88 TMK in Tikka 18” 8 twist 223. Approximately .100” FB
Virgin Starline 5.56 brass
CCI 450 primers
25 grs N540 (it’s a little hot)
2.500” COAL
DA was 0 - -500’

View attachment 1057317

Factory pipe? I'm waiting on a CTR from Euro Optics and hope the throat and magazine will allow me to shoot these 88's in it.

Jay

 

[waspocrew]

Factory pipe? I'm waiting on a CTR from Euro Optics and hope the throat and magazine will allow me to shoot these 88's in it.

Jay

My CTR 223 had a very short throat. It’s a few years old, so maybe they’ve made some changes, but you may need to extend the throat a bit yourself for the 88s to fit and not eat a ton of case capacity.

 

[Schmo]

Factory pipe? I'm waiting on a CTR from Euro Optics and hope the throat and magazine will allow me to shoot these 88's in it.

Jay

Yes sir, factory pipe. Had Kampfeld add FB

 

[Elk Wallow]

Yes sir, factory pipe. Had Kampfeld add FB

I’m curious what kampfeld charged to add freebore if you don’t mind sharing? I have a 6.5 prc with short freebore. Factory ammo is into the lands.
Thanks

 

[Schmo]

I’m curious what kampfeld charged to add freebore if you don’t mind sharing? I have a 6.5 prc with short freebore. Factory ammo is into the lands.
Thanks

It was around $100, and I think that included him shipping it back to me. That was a year ago though

 

[ID_Matt]

Before i drive myself nuts, can someone tell me what they’d recommend for the optimum twist if they had a choice? 21” 22 creed at 3500 average minimum DA. I ordered a 7.5 but now questioning it. Any draw back to a 7?

 

[glock233]

Before i drive myself nuts, can someone tell me what they’d recommend for the optimum twist if they had a choice? 21” 22 creed at 3500 average minimum DA. I ordered a 7.5 but now questioning it. Any draw back to a 7?

1:7.5 is a zen spot that does well with 62-90 grain in 22 creed. I’m shooting 80/88 ELDM and 88TMK mostly at 1500 DA.

1:7 is also fine but isn’t needed imo. Especially at your DA. You’re not missing the boat.

 

[Matt5266]

Before i drive myself nuts, can someone tell me what they’d recommend for the optimum twist if they had a choice? 21” 22 creed at 3500 average minimum DA. I ordered a 7.5 but now questioning it. Any draw back to a 7?

Im ordering a barrel soon. It will be a 7.5. Were in the same general area it looks like

 

[waspocrew]

Agree with those above - I think 7.5 is the sweet spot. My 1:8s do well, but my 7.5 Bartlein shoots the best all the way up to 95 SMK.

 

[zekepa]

For craps and giggles I loaded up a bunch of these 88s in both Nas3 and unfired Starline .223 cases, and shot them both out of a factory Tikka .223 18” barrel 1/8 twist and a 16” factory .223 barrel 1/8 twist. The 18” tube has 2-3k rounds down it and I hit lands at 2.49” COAL and the 16” tube has 2-3 hundred rounds down it, hitting lands at 2.45” COAL. I loaded the rounds to 2.43” COAL in both cases with my standard 77 TMK load,

For craps and giggles I loaded up a bunch of these 88s in both Nas3 and unfired Starline .223 cases, and shot them both out of a factory Tikka .223 18” barrel 1/8 twist and a 16” factory .223 barrel 1/8 twist. The 18” tube has 2-3k rounds down it and I hit lands at 2.49” COAL and the 16” tube has 2-3 hundred rounds down it, hitting lands at 2.45” COAL. I loaded the rounds to 2.43” COAL in both cases with my standard 77 TMK load, 23.6 XBR 8208, CCi 450 primers.

18” Starline-2690 FPS average

My 88TMKs came today made dummy rounds for my 20" 2.47 COAL and 16" 2.45 COAL, I'll redo the 16" again tomorrow, I'm a little surprised at the difference between the two chambers, but it kind of lines up with your measurements. I'd like to get to 2700fps or better with the 20" barrel using H4895, going to start with 23 gr and work up while looking for pressure.

 

[NWBLKTAIL]

My 88TMKs came today made dummy rounds for my 20" 2.47 COAL and 16" 2.45 COAL, I'll redo the 16" again tomorrow, I'm a little surprised at the difference between the two chambers, but it kind of lines up with your measurements. I'd like to get to 2700fps or better with the 20" barrel using H4895, going to start with 23 gr and work up while looking for pressure.

Are you gonna use those Nas3 cases?

I blew my first primer ever today

23gr. H4895
CCI 450
2x starline 5.56 brass
.020" off
touch over 2700 fps
22'' factory pipe Tikka

Ive shot 70 rounds if this load with no swipes, no ejector mark and primers nice and round. Could have been a total fluke, But it did happen and Im just throwing it out there as I did not expect it.

I know the Nas3 cases are suppose to be able to withstand the excess pressure, not sure if the primers will.

 

[zekepa]

I'll be using once fired LC cases. Don't have any NAS3 cases.

 

[JJ.]

Agree with those above - I think 7.5 is the sweet spot. My 1:8s do well, but my 7.5 Bartlein shoots the best all the way up to 95 SMK.

barrel length? What velocity are you running the SMK’s?

 

[waspocrew]

barrel length? What velocity are you running the SMK’s?

22” barrel. Worked up to 2960 with H4350. Will likely revisit them again with RL-26.

 

[zekepa]

Shot 3rds of each load below. No signs of pressure, I can see, although I pretty sure they would be over book max, if the 88TMK had load data for .223

.223 T3x 20" 1 in 8 factory barrel with Banish 30V2 suppressor using Pods magazine.

88TMK
2.43 COAL
1x fired LC brass
7.5 Rem Primer

H4895 23.0 gr avg 2632
H4895 23.5 gr avg 2679
H4895 24.0 gr avg 2740

Have 10 loaded at 24.0 gr for when I can get to the range. Shot the above in my backyard at 50 yds to get velocity readings.

 

[Hill Difficulty]

Friendly 88 TMK summary/where I ended up on load dev:

• 23.6 grains of H4895, so 59,000+ (ballpark psi calculation)
• 2.52" OAL, just under .030" jump, no sense of powder compression at 23.6 grains
• 2,703 fps average (last 10-round spread 2,691 to 2,017 )
• 223 Rem Lapua Match headstamp, new brass
• 17" barrel w/ 1:7 rot, suppressed, .090 freebore
• CCI 450 MSRP

Notes: Very accurate and easy to load for. Same 100 yard POI from 21 to 24.5 grains. Went to 24.5 with no visible or measurable pressure indicators whatsoever. Backed down to 23.6 to keep under 60,000 psi.

Thoughts: Initial gut sense on the 88 TMK in 223 Rem was the lengthy bullet would use up too much case volume. Ended up being much faster than expected - very pleased with ease of loading and longer range trajectory (vs 75 and 80 eld). Will hunt with this bullet in 2026. Gonna be in TX next week. For curiosity, planning to load a few 88 TMKs with RL26 for 1:8 22CM w/22" barrel. For the sake of case volume and pressure safety am suggesting longer throat/extended seating length for anyone considering this bullet in a 223 Rem.

 

[KyleR1985]

Friendly 88 TMK summary/where I ended up on load dev:

• 23.6 grains of H4895, so 59,000+ (ballpark psi calculation)
• 2.52" OAL, just under .030" jump, no sense of powder compression at 23.6 grains
• 2,703 fps average (last 10-round spread 2,691 to 2,017 )
• 223 Rem Lapua Match headstamp, new brass
• 17" barrel w/ 1:7 rot, suppressed, .090 freebore
• CCI 450 MSRP

Notes: Very accurate and easy to load for. Same 100 yard POI from 21 to 24.5 grains. Went to 24.5 with no visible or measurable pressure indicators whatsoever. Backed down to 23.6 to keep under 60,000 psi.

Thoughts: Initial gut sense on the 88 TMK in 223 Rem was the lengthy bullet would use up too much case volume. Ended up being much faster than expected - very pleased with ease of loading and longer range trajectory (vs 75 and 80 eld). Will hunt with this bullet in 2026. Gonna be in TX next week. For curiosity, planning to load a few 88 TMKs with RL26 for 1:8 22CM w/22" barrel. For the sake of case volume and pressure safety am suggesting longer throat/extended seating length for anyone considering this bullet in a 223 Rem.

Barrel length?

 

[Hill Difficulty]

Barrel length?

Barrel length is 17 inches.