Sticky Bolt with Accurate Load

73driver

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Thank you. IMR 4451 load data shows 41.9 as max load. 39.5 seems like a low charge. How does it arrive at that number.
Different rifles will give you different pressure/velocity results from what is in manuals. I had 2 30-06's, one gave me great MV and decent accuracy at just under max published load. In my other rifle the same load resulted in pressure results like yours, stiff bolt and ejector marks. The load data is developed with TEST Barrels. I would think a test barrel would be selected to be around mid SAMMI specifications for bore and chamber. Neither too tight or two sloppy. In the everyday retail world we buy rifles that have the possibility of being of tighter or looser dimensions than "TEST" barrels, thus we can not expect we can always achieve results that match the published loading manuals.
 

General RE LEE

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I am not sure what you mean by slow barrel unless you mean slower barrel twist. A twist rate is for bullet stabilization, and a faster twist does not necessarily mean more velocity. I have SAKO M995 1:11" 24" that is propelling the 190 Berger VLD at 3043 FPS with 75 H4831SC, no slouch in my opinion.

Does Twist Rate Make a Difference in Velocity? Yes. Our tests show that, with the 80-90gr bullets, a 1:10 or 1:12 barrel will give you as much as 80fps more velocity than a 1:8 barrel, shooting the exact same loads. Fast twist (1:8) barrels have more drag and friction, which can slow the bullet down. Ideally you want to use the slowest twist rate possible that will stabilize the bullet you choose to shoot. For a dedicated "point-blank" 100/200 yard Benchrest gun, you want a twist rate from 1:13 to 1:15. But if you want to shoot both light (60-80gr) and heavy (100gr+) bullets, stick with a 1:8.
(SOURCE: https://www.6mmbr.com/barrelfaq.html)


I am surprised that's all the velocity you're able to generate out of 168g VLD. I am propelling the 190 Berger VLD out of my .30 Gibbs 1:10" 24"

4-shot series, 57 RL17: AVG = 2806, ES = 15, SD = 6

1) no I'm not talking about barrel twist I'm talking about velocities out of Tikka barrels. There is quite a bit of feedback from Tikka owners their barrels don't get expected velocities but they are very accurate for a stock rifle.

2) My 7mm STW load was not intended to be a fast load. It's got a low ES and SD, milder recoil and good velocity for where I'm hunting plus it grouped sub MOA at 100 yards.
 

RYEWSKY25284

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6.5 Creedmoor
IMR 4451 42.0 grains
143 grain ELD-X
.3 MOA accuracy
Stiff bolt lift and light ejector Mark Tikka T3x
.015 off lands

Should I drop down .3 grains to 41.7 grains?
How do you think it will shoot on a hot day?? I'm not sure 4451 is temp stable. Could be a blast..:-(
pull it back .2 or .3gr and reset seating depth. I think you will find the equal accuracy and not have the worry of a terminal failure.

my .02 cents
 

General RE LEE

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How do you think it will shoot on a hot day?? I'm not sure 4451 is temp stable. Could be a blast..:-(
pull it back .2 or .3gr and reset seating depth. I think you will find the equal accuracy and not have the worry of a terminal failure.

my .02 cents

Thank you I've got it seated 0.015 off the lands. I will bump back to 0.030 off the lands and try 40.7, 41, 41.3 and 41.5 grains and watch for pressure. I think somewhere in there is a good hunting load.
 

FEENIX

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1) no I'm not talking about barrel twist I'm talking about velocities out of Tikka barrels. There is quite a bit of feedback from Tikka owners their barrels don't get expected velocities but they are very accurate for a stock rifle.
Slower compared to what? Reloading manual, #s from factory ammo box, etc? I read quite a bit of those posts that are blanket statements or someone read them on the internet.

I read a post at the Hide (not a member). A member shot a factory American Gunner ELDM and got 2650 FPS from Tikka CTR with factory 24" barrel. Same ammo was shot from another rifle with a 26" Bartlein custom barrel and yielded 2700 FPS.

I have yet to see a quantifiable and authoritative claim. Someone told me the same claim about factory SAKO M995.

Anywho...
 
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General RE LEE

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Slower compared to what? Reloading manual, #s from factory ammo box, etc? I read quite a bit of those posts that are blanket statements or someone read them on the internet.

I read a post at the Hide (not a member). A member shot a factory American Gunner ELDM and got 2650 FPS from Tikka CTR with factory 24" barrel. Same ammo was shot from another rifle with a 26" Bartlein custom barrel and yielded 2700 FPS.

I have yet to see a quantifiable and authoritative claim. Someone told me the same claim about factory SAKO M995.

Anywho...

Slower speeds than published load data in manuals. Lot's of feedback Tikka barrels run slow. These are just a few there are many more.




 

Old rooster

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cabelasken send that back to RCBS and they will re-calibrate it or replace it.If it was made by Pact they will send it to them and they will fix it.
several years ago I bought the Pact digital scale and had problems like you mentioned but was off by 3.0 grains.
I sent it back to Pact and they fixed it.
I was not at max loads as I got a positive node at 52.0 grains of IMR 4350 for a 180 gr Interbond but the first shot stung my hands so I knew it was over.
Like you I keep my 10-10 RCBS close by and found the error,
smart move,I can tell your experienced.
Have a great day.
Old Rooster
 

jgs8163

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I would change your seating depth. I think you’re too close and may be causing added pressure. Back off to .030-.040 and reduce charge. I don’t think you’ll see much change in accuracy. 4451 is very temp stable and I ran it with a 129 ABLR into the 2900 FPS area out of a Kimber. If you have access to RL26 it’s going to get you into the 2900 FPS area with the 143 ELDX. Max load in Hornady manual shows 41.3 for 4451 and 143ELDX.
 
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FEENIX

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Slower speeds than published load data in manuals. Lot's of feedback Tikka barrels run slow. These are just a few there are many more.




Yep, I read them. I had plenty of published load data that ran a lot slower too non-Tikka with factory barrel and custom barrels.
 

Old rooster

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jgs8163 isn't it just the way things go that we need a powder we don't have?
I have many 1 lb bottles of powder and I need many more than I have.
Re26 is my short list.
Old Rooster
 

jgs8163

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jgs8163 isn't it just the way things go that we need a powder we don't have?
I have many 1 lb bottles of powder and I need many more than I have.
Re26 is my short list.
Old Rooster
Absolutely. I’m fortunate enough to have bought a couple of Kegs of 26 about a year and a half ago. Things are quite crazy now with supplies but I think it’s beginning to calm some.
 

Seabeeken

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Thank you. IMR 4451 load data shows 41.9 as max load. 39.5 seems like a low charge. How does it arrive at that number.
Yes but I doubt they were .015" off the lands. 4451 peaks out quickly and signs come on suddenly. By the time you see ejector marks, you are usually over 70,000 psi. Learned this with my 250AI.
 

General RE LEE

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I would change your seating depth. I think you’re too close and may be causing added pressure. Back off to .030-.040 and reduce charge. I don’t think you’ll see much change in accuracy. 4451 is very temp stable and I ran it with a 129 ABLR into the 2900 FPS area out of a Kimber. If you have access to RL26 it’s going to get you into the 2900 FPS area with the 143 ELDX. Max load in Hornady manual shows 41.3 for 4451 and 143ELDX.

I agree. I’ve taken multiple Hornady OAL measurements with a once fired modified case and I seated 0.015 off lands so maybe it’s seating depth and charge.
 

General RE LEE

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Yes but I doubt they were .015" off the lands. 4451 peaks out quickly and signs come on suddenly. By the time you see ejector marks, you are usually over 70,000 psi. Learned this with my 250AI.

I’m on a learning curve. So you can get pressure spikes even off the lands like 0.010 or 0.015? I thought I was safe cause I wasn’t in the lands.
 

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