Play with Seating Depth or something else

Pineman

Beginner
Dec 20, 2021
74
87
So I did a couple of ladder tests for my 270 WSM with the Federal TA 136g. I worked up the same load with Remington Brass and virgin ADG brass. Went to the range today and shot the 2 groups. The Remington brass grouped 1.983 with and ES of 11 and SD of 4. The virgin ADG brass load grouped 1.776 with and ES of 8 and SD of 3. My question : since the ES and SD are very good, do you think I need to play with seating depth or tweak the powder charge? With other handloads in 130,140 and 150 grain it consistently with shoot around 1/2 inch. This is one of my winter projects to find a load for the 136TA.
TIA
 
So I did a couple of ladder tests for my 270 WSM with the Federal TA 136g. I worked up the same load with Remington Brass and virgin ADG brass. Went to the range today and shot the 2 groups. The Remington brass grouped 1.983 with and ES of 11 and SD of 4. The virgin ADG brass load grouped 1.776 with and ES of 8 and SD of 3. My question : since the ES and SD are very good, do you think I need to play with seating depth or tweak the powder charge? With other handloads in 130,140 and 150 grain it consistently with shoot around 1/2 inch. This is one of my winter projects to find a load for the 136TA.
TIA
I'd work on seating depth changes in increments of .015" to see if groups shrink.

BTW - I think you're the first poster that I've ever seen list his group size down to the 1/1,000 of an inch. :D
 
Yes, I'm happy with the velocity. My Browning's like quite a bit of jump so would you try seating slightly shorter first or seat a group .015 shorter and 0.15 longer and try again?
 
So I did a couple of ladder tests for my 270 WSM with the Federal TA 136g. I worked up the same load with Remington Brass and virgin ADG brass. Went to the range today and shot the 2 groups. The Remington brass grouped 1.983 with and ES of 11 and SD of 4. The virgin ADG brass load grouped 1.776 with and ES of 8 and SD of 3. My question : since the ES and SD are very good, do you think I need to play with seating depth or tweak the powder charge? With other handloads in 130,140 and 150 grain it consistently with shoot around 1/2 inch. This is one of my winter projects to find a load for the 136TA.
TIA
How far is your jump into the rifling now?

That size of a grouo
you need to work on both charge and depth
 
I'm currently about 0.070 jump. I was using Fed 215 and Fed 215 Match primers. I've had good luck in the past with Fed 210, WLRM and Rem 9.5M primers.
I might try a different primer along with different seating depths and compare to this baseline. This is part of the fun for me..
 
Have you ran 3 shot groups in .3 grain increments and see what the paper tells you? You should be able to find a node within those groups. What powder are you using in this test?
 
TackDriver284
I'm using RL 17 as per Federals recommended powders. I found a good velocity node during my ladder test on 0.2 grain increments. The loads I worked up are with one of the nodes at the higher 0.2 grains. I haven't tried the lower 0.2 grain node yet.
 
I’m not familiar with the bullet itself but reading your post again, you’ve a 1/2 moa rifle that doesn’t appear to like the federal bullet. While this is a great time to experiment, lot of time until opening day, I wouldn’t waste Rl 17 on to many more efforts. That stuff is gold. Any way, I too would try going a little shorter and using once fired brass. Once fired makes a significant improvement in one of my rifles. As I proof my writing, you have a rifle capable of 1/2 in several loadings. Not sure you could have an issue addressed with fire forming. If all else fails try an AccuBond.
Good luck.
 
Looking forward to your results, as I have also acquired some component 136 gr TA's to try in my 270 WSM. (Browning X Bolt factory 23" barrel)
(To date of the factory ammo I have tried in my rifle, The Federal 140 gr Trophy Bonded Tip produces 0.396" groups @ 3156 fps, the Nosler 140 gr AccuBond produces 0.565" groups @ 3073 fps, and the Federal 130 gr Power Shock produces 1.472" groups @ 3228 fps. 3-shot Groups @ 100 yards)
I do have the Federal Terminal Ascent factory ammo as well, and have yet to try them in the rifle to see how they perform. If they work great, then I'll try to start with the same COAL. (Am hoping to get to range tomorrow as it is supposed to 2 degrees C here, to try the Federal TA ammo in my 6.5 PRC, 270 WSM and 7mm Rem Mag. The last time I was trying to get there didn't happen) I will note that the Standard Deviation for the Federal Terminal Ascent ammunition in my 6.5 Creedmoors (Browning X Bolt and Winchester High Wall) and 270 Win (Steyr Mannlicher) have been 13.5, 11.5, and 15 fps, respectively. The 300 WSM (custom Rem 700) was the worst at 56 fps, and produced 1.366" groups - while not sb-MOA like the others, still accurate enough for my typical hunting (although that rifle's favourite load is with WXR and 180 gr AccuBonds for 0.442" groups), and the first ammo/load ever shot in the rifle that wasn't sub-MOA. I need to try gain to ensure that it isn't the ammo and was just me that day)
I'm fortunate that I have a decent supply of Re-17 on hand for this, along with the other powders listed below. (In talking to the technician at Federal's Custom Shop, I can verify that he stated that this was the preferred powder for this bullet in this cartridge for producing ammunition.)

Here is the data I have found for this bullet in the 270 WSM (All charges max, with the first row being the factory ammunition spec for comparison):
BC SD COAL Primer Powder Charge (Max) FPS Ft. Lbs.
FederalTerminal Ascent
136​
0.493​
0.253​
3240​
3170​
Terminal Ascent
136​
0.493​
0.253​
Terminal Ascent
136​
0.493​
0.253​
2.860​
F215MagPro
74.3​
3293​
3274​
Terminal Ascent
136​
0.493​
0.253​
2.860​
F215Re-26
67.7​
3270​
3229​
Terminal Ascent
136​
0.493​
0.253​
2.860​
F215Re-17
61.1​
3259​
3207​
Terminal Ascent
136​
0.493​
0.253​
2.860​
F215Re-22
64.9​
3229​
3148​
Terminal Ascent
136​
0.493​
0.253​
2.860​
F215N560
67.5​
3229​
3148​
Terminal Ascent
136​
0.493​
0.253​
2.860​
F215Re-19
64.7​
3222​
3135​
Terminal Ascent
136​
0.493​
0.253​
2.860​
F215Hunter
65.2​
3205​
3105​
Terminal Ascent
136​
0.493​
0.253​
2.860​
F215H4831
68.0​
3201​
3094​
 
Looking forward to your results, as I have also acquired some component 136 gr TA's to try in my 270 WSM. (Browning X Bolt factory 23" barrel)
(To date of the factory ammo I have tried in my rifle, The Federal 140 gr Trophy Bonded Tip produces 0.396" groups @ 3156 fps, the Nosler 140 gr AccuBond produces 0.565" groups @ 3073 fps, and the Federal 130 gr Power Shock produces 1.472" groups @ 3228 fps. 3-shot Groups @ 100 yards)
I do have the Federal Terminal Ascent factory ammo as well, and have yet to try them in the rifle to see how they perform. If they work great, then I'll try to start with the same COAL. (Am hoping to get to range tomorrow as it is supposed to 2 degrees C here, to try the Federal TA ammo in my 6.5 PRC, 270 WSM and 7mm Rem Mag. The last time I was trying to get there didn't happen) I will note that the Standard Deviation for the Federal Terminal Ascent ammunition in my 6.5 Creedmoors (Browning X Bolt and Winchester High Wall) and 270 Win (Steyr Mannlicher) have been 13.5, 11.5, and 15 fps, respectively. The 300 WSM (custom Rem 700) was the worst at 56 fps, and produced 1.366" groups - while not sb-MOA like the others, still accurate enough for my typical hunting (although that rifle's favourite load is with WXR and 180 gr AccuBonds for 0.442" groups), and the first ammo/load ever shot in the rifle that wasn't sub-MOA. I need to try gain to ensure that it isn't the ammo and was just me that day)
I'm fortunate that I have a decent supply of Re-17 on hand for this, along with the other powders listed below. (In talking to the technician at Federal's Custom Shop, I can verify that he stated that this was the preferred powder for this bullet in this cartridge for producing ammunition.)

Here is the data I have found for this bullet in the 270 WSM (All charges max, with the first row being the factory ammunition spec for comparison):
BC SD COAL Primer Powder Charge (Max) FPS Ft. Lbs.
FederalTerminal Ascent
136​
0.493​
0.253​
3240​
3170​
Terminal Ascent
136​
0.493​
0.253​
Terminal Ascent
136​
0.493​
0.253​
2.860​
F215MagPro
74.3​
3293​
3274​
Terminal Ascent
136​
0.493​
0.253​
2.860​
F215Re-26
67.7​
3270​
3229​
Terminal Ascent
136​
0.493​
0.253​
2.860​
F215Re-17
61.1​
3259​
3207​
Terminal Ascent
136​
0.493​
0.253​
2.860​
F215Re-22
64.9​
3229​
3148​
Terminal Ascent
136​
0.493​
0.253​
2.860​
F215N560
67.5​
3229​
3148​
Terminal Ascent
136​
0.493​
0.253​
2.860​
F215Re-19
64.7​
3222​
3135​
Terminal Ascent
136​
0.493​
0.253​
2.860​
F215Hunter
65.2​
3205​
3105​
Terminal Ascent
136​
0.493​
0.253​
2.860​
F215H4831
68.0​
3201​
3094​
 
TackDriver284
I'm using RL 17 as per Federals recommended powders. I found a good velocity node during my ladder test on 0.2 grain increments. The loads I worked up are with one of the nodes at the higher 0.2 grains. I haven't tried the lower 0.2 grain node yet.
Looks like you did your homework finding a good node to work with. I’m thinking your barrel isn’t taking to those Federals.
 
I have never personally seen my best accuracy jumping bullets, velocity yes, accuracy never. But I never run a seating test changing .015" at a time, maybe thats why.

I never change my seating depth more than .005" if I am serious about finding my "optimum" seating depth for any given bullet. I also start any new load development .005 - .008" into the lands. This gives easy bolt down on the cartridge, and at that depth I start with a starting load and work up to max, "FOR MY PARTICULAR GUN".

Once I find my top load I start with a 3 shot test group from 1.5 grains below max, I have never found my accuracy with under pressured loads, usually max, or close. I also have seen where i could miss an optimum depth going more than .005: at a time. But maybee my starting depth is why. Once those three shot groups tell me what it likes best, I start coming off my lands .003" at a time. I would never change more than .005" at a time if I were looking for a best load! Once I find I my best depth, I will load up and down .3 of a grain in medium to large capacity cases, anything using more than 30 grains. Yes up and down, as the farther I come off the lands lhe less pressure I am getting, as my velocity goes up to certain length, then levels off.

I in over 50 years have only had one rifle shoot BETTER off a light touch, and that is a 222 Remington Bench Rest rifle on a Panda action. The only one, from 17 Mach IV to 338 WM. Just my personal experience. But I have stayed with extruded powders, mainly IMR, Hodgdon, and Vihtavuori. This has just been my experience using the tuning method I mentioned.
 
Thanks for the replies. I won't get to try and changes for a couple of weeks and maybe it will be warmer than 15 degrees next time I shoot at the range!!
 
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