Sierra TMK 175g ( .308 ) seating depth?

Cpt.Flan

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Hi guys!

I am a 175 SMK user in my AIAX set up .308 custom rifle.

I am running my reloads at around 18 to 20 thousands from the lands with great success. With them at 20 thousands from lands they will still fit perfectly in my AI mags. ( max of 2.880 )

Now if I repeat the process and want to run the TMK at the same jump length I realized that they will no longer fit in my mags. Way over 2.880!

I understand that the ogive design is different and will obviously be touched by the lands when loaded longer.


Now the question is?

1- Have you guys tried the TMK's ?
2- Did you notice any accuracy difference by reloading them mag length with a BIG JUMP?

3- Apparently this new design is less jump sensitive. Is this true from your experience?

Thank you very much guys!


P.S. Waiting on this to press the checkout button or not... lol
 
Hi guys!

I am a 175 SMK user in my AIAX set up .308 custom rifle.

I am running my reloads at around 18 to 20 thousands from the lands with great success. With them at 20 thousands from lands they will still fit perfectly in my AI mags. ( max of 2.880 )

Now if I repeat the process and want to run the TMK at the same jump length I realized that they will no longer fit in my mags. Way over 2.880!

I understand that the ogive design is different and will obviously be touched by the lands when loaded longer.


Now the question is?

1- Have you guys tried the TMK's ?
2- Did you notice any accuracy difference by reloading them mag length with a BIG JUMP?

3- Apparently this new design is less jump sensitive. Is this true from your experience?

Thank you very much guys!


P.S. Waiting on this to press the checkout button or not... lol
 
Hi guys!

I am a 175 SMK user in my AIAX set up .308 custom rifle.

I am running my reloads at around 18 to 20 thousands from the lands with great success. With them at 20 thousands from lands they will still fit perfectly in my AI mags ( 2.900" from the inside ). ( max of 2.880 for the cartridge OAL )

Now if I repeat the process and want to run the TMK at the same jump length I realized that they will no longer fit in my mags. Way over 2.880!

I understand that the ogive design is different and will obviously be touched by the lands when loaded longer.


Now the question is?

1- Have you guys tried the TMK's ?
2- Did you notice any accuracy difference by reloading them mag length with a BIG JUMP?

3- Apparently this new design is less jump sensitive. Is this true from your experience?

Thank you very much guys!


P.S. Waiting on this to press the checkout button or not... lol
 
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175 SMK's are a jump tolerant bullet so the TMK should be similar. More than likely you will have to develop a new load and play around with seating depth as the TMK is a different bullet . Might not be as simple as swapping them out.

Is this an AX rifle? The AX mag should be 2.980 OAL inside the mag. Aics mag is 2.880 OAL.
 
The 69's are running good at 10 thou for me, but Im going to play around with the depth sometime and see how if effects the SD.
 
The 69's are running good at 10 thou for me, but Im going to play around with the depth sometime and see how if effects the SD.

Now that I have a new magazine that will handle seating them longer, I will do more testing, but that won't happen until my basement development is finished, and I can unpack my loading gear.
 
My 308 AX mags are exactly 2.900" from the inside. I figured 2.880 would be correct as the max cartridge OAL.
 
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Once you do, you should start a thread. I would like to hear your thought on it all. Dont wanna hijack this thread. :)

Right now without any tweakin Im sitting at a SD of 13 and would like to get that down to 10 or under.
 
I load the 175gr Tmk's in my AIAT and just load them to mag length (2.880). Haven't loaded any rounds that shot over MOA, and most sub half or better. I had a thread going earlier where you can see my progress as I developed loads.
 
I think the original poster has a AIAX chassis and non-AI action?

AI's have tight chambers. A custom gun can be built to whatever spec.

With that said, I've seen the TMK 175 shoot very well out of a remington 5R. Remingtons have extremely long chambers (I load my 208gr well over 3" long).

Testing on YOUR rifle will determine it's limits.

I'll likely be running 175 SMK's in my AIAT, but also want to see what performance the Berger VLD 175's will do.
 
I load the 175gr Tmk's in my AIAT and just load them to mag length (2.880). Haven't loaded any rounds that shot over MOA, and most sub half or better. I had a thread going earlier where you can see my progress as I developed loads.

Your AIAT's mag has an internal capacity of 2.980 (AW,AX double stack mags). The 2.880 capacity if for single stack aics mags. The OP would not be able to load his rounds as far out as you can unless he has an actual AIAX.
 
Your AIAT's mag has an internal capacity of 2.980 (AW,AX double stack mags). The 2.880 capacity if for single stack aics mags. The OP would not be able to load his rounds as far out as you can unless he has an actual AIAX.

Well that's good to know! Guess I should measure my chamber and adjust my seating depth
 
Your AIAT's mag has an internal capacity of 2.980 (AW,AX double stack mags). The 2.880 capacity if for single stack aics mags. The OP would not be able to load his rounds as far out as you can unless he has an actual AIAX.

Well, that's interesting. So an action that accepts the double stack mags like a Stiller Spectre or Defiance Deviant would allow a bit longer AOL in .308 if the chamber was cut to match and still mag feed. I shoot a lot of federal GMM 175 loads and I'm super interested in the 175 grain Berger but I don't like single loading the heavier bullet loads. Wish one of those actions came with a field strippable bolt like the AI, PGW Coyote, etc.
 
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Well, that's interesting. So an action that accepts the double stack mags like a Stiller Spectre or Defiance Deviant would allow a bit longer AOL in .308 if the chamber was cut to match and still mag feed. I shoot a lot of federal GMM 175 loads and I'm super interested in the 175 grain Berger but I don't like single loading the heavier bullet loads. Wish one of those actions came with a field strippable bolt like the AI, PGW Coyote, etc.

Yes they certainly would. Another action that takes AW mags is the new GAP Tempest from GA Precision.
 
Hey SJ I thought I would post this here since we were talking about it and this thread is just one of the three the OP made.

I know that every rifle has its on personalities and all, but I thought I was pass this along anyways.

Went out today and tried out a few different things.

varget 25.5gr
10thou jump (ogive 1.894)
sd:13
es:27

today
20thou
3056,3044,3042fps
sd:7
es:14

30thou
3022,3053,3039fps
sd:15
es:31



varget 25.6gr
3078,3085,3075fps
10thou
sd:5
es:10

varget 25.7gr
3086,3081,3110fps
10thou
sd:16
es:30

I know its only three rounds, but its a start.
 
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I need to try the tmks in my 700p also. Throat is so long ill try a few different lengts with a medium load and see how they shoot, and then tune the powder load i guess.
 
I like them and they seem to be shooting pretty good for me to, as long as I do my part. Sometimes i just lose focus and try muscling them into a group and it really shows. heh

But Im still having fun playing around with these.
 
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I ran mine at a few diff lengths - TMK 175's - tried jammed and out, and book length worked best which ends up being 2.80 COL. Shot the best that way
 
I can't really add anything to the other posts here except that I use 168 TMK's with great success in my K31. They fit the mag no problem and easily seat all the way into the lands without being too short OAL. Regular SMK's have to be seated too deep into the case just to fit the chamber.
 
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