95 tmk issues in 6 creed

[FowlMouthA400]

I know there is another post about them that’s recent but I didn’t want to hijack someone else’s post with my issues.

So I got a batch of these to try and in 2 guns I’m starting to hit pressure at 41.5 grains of 4350 with Peterson brass. 42 grains is very heavy bolt lift and shaving brass off the head stamp.

Reading @Formidilosus comment about them being seated closer to 2.6 makes me think I need to seat them farther in to bleed off some pressure. I have them seated about 2.75 I think.

Two guns are, Seekins ph3 24” bbl and running about 2900 And a ruger American gen 2 with a 20” barrel and they were about 2850.

Anyone else had this issue? Book max is 43.1 from sierra

 

[5MilesBack]

Are you using a suppressor?

 

[FowlMouthA400]

Are you using a suppressor?

Of course

 

[Nine Banger]

My buddy has a seating tool that he brought to the range the other day.

We saw velocity increase when he seated bullets in further so I bet if you make your cartridges shorter that you will increase pressure instead of decreasing it.

I shot a bunch of 95tmks with 43.5gr H4350 at 2.680 and 2.770 and they were fine thru a barrel in which the chamber is too long to seat near the lands.

 

[5MilesBack]

Of course

I shot some UM .243 108gr ELDM loads in my Tikka unsuppressed and just had a little hard bolt lift. Then when I shot them with a suppressor on, the loads were blowing primers out and have heavy ejector indentations on the brass.

 

[FowlMouthA400]

I shot some UM .243 108gr ELDM loads in my Tikka unsuppressed and just had a little hard bolt lift. Then when I shot them with a suppressor on, the loads were blowing primers out and have heavy ejector indentations on the brass.

That’s lame….dont want to shoot them if I can’t use the suppressor

 

[wind gypsy]

Peterson 6 Creedmoor Brass is smaller capacity than hornady, alpha, lapua. It's probably closer to 6 XC capacity than it is hornady 6 creedmoor brass (which most load manuals seem to be based on).

Thus, "book max" is going to be hot in your brass. There have been other posts on the forum about pressure issues treating peterson 6 creed brass like it's hornady/lapua/alpha.

 

[FowlMouthA400]

Peterson 6 Creedmoor Brass is smaller capacity than hornady, alpha, lapua. It's probably closer to 6 XC capacity than it is hornady 6 creedmoor brass (which most load manuals seem to be based on).

Thus, "book max" is going to be hot in your brass. There have been other posts on the forum about pressure issues treating peterson 6 creed brass like it's hornady/lapua/alpha.

Kind of what my research was leading me to…I’ll try them in Hornady or starline and see how it does

 

[ID_Matt]

Peterson 6 Creedmoor Brass is smaller capacity than hornady, alpha, lapua. It's probably closer to 6 XC capacity than it is hornady 6 creedmoor brass (which most load manuals seem to be based on).

Thus, "book max" is going to be hot in your brass. There have been other posts on the forum about pressure issues treating peterson 6 creed brass like it's hornady/lapua/alpha.

I thought the same but his velocity was quite a bit lower than what i'd expect too so something really seems off to me.

 

[wind gypsy]

I thought the same but his velocity was quite a bit lower than what i'd expect too so something really seems off to me.

Good call. I missed that. Definitely more than just a capacity issue.

 

[Travis h]

Kind of what my research was leading me to…I’ll try them in Hornady or starline and see how it does

Great info

 

[MT762]

Seating depth will change pressure, if you seat way deep pressures will go up almost like touching the lands.

Also when was the last time you looked for a carbon ring?

 

[FowlMouthA400]

Seating depth will change pressure, if you seat way deep pressures will go up almost like touching the lands.

Also when was the last time you looked for a carbon ring?

Seating depth was longer than book and highly doubt a carbon ring in a barrel with less than 300 rounds.

 

[ResearchinStuff]

Is your jump less than your shoulder setback? If so, the firing pin will Jam the bullet and pressure spikes early.

 

[FowlMouthA400]

Is your jump less than your shoulder setback? If so, the firing pin will Jam the bullet and pressure spikes early.

No I’m still under 2.7500 coal nowhere near 2.8 for the cartridge. I tried to find the lands with the bullet and that tool from Hornady and there wasn’t enough of the bearing surface to hold it in the case. I’m 99% sure it’s just the thicker brass causing issues…almost every bullet in put in Peterson cases I hit pressure early

 

[mthayr]

Do you have a bump neck bushing? Does fire formed brass with the neck bumped back .002" behave the same (slightly more volume)?

 

[AZ Gator]

Are you using h4350 or imr4350?

Regardless of pressure issues, I’m surprised your speeds are so low. Out of a 16” barrel (6CM) with the 95TMK, I get 2975 with 43.0gn and 2930 with 42.0 gn.

 

[FowlMouthA400]

I do n

Do you have a bump neck bushing? Does fire formed brass with the neck bumped back .002" behave the same (slightly more volume)?

I do not

 

[FowlMouthA400]

Are you using h4350 or imr4350?

Regardless of pressure issues, I’m surprised your speeds are so low. Out of a 16” barrel (6CM) with the 95TMK, I get 2975 with 43.0gn and 2930 with 42.0 gn.

H4350….next week I’ll have time to try them in Hornady or starline brass to see how they do