Sierra Heavy TMK 20 Cal (.204 DIA) Testing

[Nine Banger]

The new 58gr TMK is showing a lot of promise right off the rip.

Test Target 1:

.204 Ruger 3433fps
24.5gr 8208 XBR 2.260" OAL
SWFA 3-9x
1:9.5 twist 16” bbl
OG 20





Test Target 2:

20 Creedmoor 4140fps
39gr H4350 2.405" OAL
Maven RS1.2
1:10 twist 18” bbl
OG 20





@Formidilosus @longrangelead @Ryan Avery

 

[RWT]

4K and the TMK is holding together. Impressive. Is it the twist rate that allows this?

 

[joshdidthis]

Shows a lot of promise. What's the bc on the bullet and when it's it getting released?

 

[Gstew1930]

 

[Q_Sertorius]

Can you shoot a .224 bullet through that OG 20?

 

[Axlrod]

Shows a lot of promise. What's the bc on the bullet and when it's it getting released?

Once a year, on this date. Along with the OG20

 

[TradLife406]

The new 58gr TMK is showing a lot of promise right off the rip.

Test Target 1:

.204 Ruger 3433fps
24.5gr 8208 XBR 2.260" OAL
SWFA 3-9x
1:9.5 twist 16” bbl
OG 20

View attachment 1045861



Test Target 2:

20 Creedmoor 4140fps
39gr H4350 2.405" OAL
Maven RS1.2
1:10 twist 18” bbl
OG 20

View attachment 1045860



@Formidilosus @longrangelead @Ryan Avery

Wait a, a 20 creed?
How's it do on game?

 

[JordanM]

Good shooting brother. Who cut those barrels? Can you post up reemer specs?

 

[43.6N]

20creed +P. hmmmm…looks like it’s bussin!

I’ve got an African safari im taking next April 1st.
Sounds like a good chambering for baboon and Cape buffalo.
Don’t mind if I steal your load data do ya?

 

[Fireflyfishing]

This would be more believable if it were a 17 CM…

 

[Gstew1930]

 

[JordanM]

Garrett those groups don’t lie! You probably already have a 20 creed getting spun up anyway.

 

[Gstew1930]

Garrett those groups don’t lie! You probably already have a 20 creed getting spun up anyway.

. Ive got some property you need to buy

 

[ztc92]

Man I hope this blows up and then Sierra decides to actually do it. What a great story that would be!

 

[rbutcher1234]

See if this wasn’t fake and a heavy tmk for a .204 ruger actually existed, I would actually do this. Lol

 

[Chris in TN]

Related, but not really worth its own thread:

Hornady Says It Will Phase Out Creedmoor and PRC Cartridges, Shifts Focus to Proven Classics

 

[gabenzeke]

There's a guy I saw a while back that did build a 20 creed and was getting more than 5k fps with 55 grain bergers.

Sent from my Pixel 9 Pro XL using Tapatalk

 

[schmidty3]

The new 58gr TMK is showing a lot of promise right off the rip.

Test Target 1:

.204 Ruger 3433fps
24.5gr 8208 XBR 2.260" OAL
SWFA 3-9x
1:9.5 twist 16” bbl
OG 20

View attachment 1045861



Test Target 2:

20 Creedmoor 4140fps
39gr H4350 2.405" OAL
Maven RS1.2
1:10 twist 18” bbl
OG 20

View attachment 1045860



@Formidilosus @longrangelead @Ryan Avery

20 creed? 4100 fps? Who hurt you?

 

[MTSLW]

I wish this was true!

 

[ChrisAU]

20 Creed is too overbore IMO, I can get 3800 fps out of my 20GT that's all one needs. Bunch of wasteful barrel burners in this thread.