Any (7mm-08 / H414 [or 760] / 139SST) 1st hand experience?

[nkyshooter]

I recently got a B&C stock to drop my Savage 7mm-08 sporter into and saw undeveloped handloads move from over 1.5" at 100 to well under an inch (.7-.8ish). Very encouraged with the improvements so now I've begun some true load development for this setup. FYI - always looking to learn more but I'm a very experienced reloader and have experience with reading cases/bolt lift for pressure signs.

I built a ladder charge using the 139 SST's I had on hand (.486 G1 BC) and H414 which I have a good deal of (I know, not ideal for temp stability but has never given me issues personally) ...

I used data from Hornady 11th edition (mobile app) which shows max charge of 49.9g. @ 2900fps

• Hornady FL sized, trimmed, weight sorted all cases weighing within .2gr of one another
• CCI-BR2 primer
• Savage 10
• Savage factory sporter 22" barrel (do not know the twist rate)
• Sunshine, slight breeze, 45 deg F - firing from bench in shade under the roof over the firing line

I started at 46.7 and moved up in increments of .3g. The top 3 or 4 charge weights were definitely compressed some.

I started at the bottom and the chronograph clocked the 46.7, 47.0, 47.3, 47.6, & 47.9g loads between 3000-3050fps. - I wasn't expecting any pressure signs down here since I was starting out a good bit below max (6.5%) but I was NOT expecting velocities near that high. The Hornady 11th ed shows 47 grains should put the velocity somewhere around 2750 fps (with a 24" bbl while mine is just a 22"bbl)

I had loaded the ladder to book max (49.9g according to Hornady 11th) plus a couple more (last/highest at 50.6g), planning to stop when an ejector mark arrived at the party ... No stiff bolt, no marks, no primer craters, etc so I continued and saw velocities increasing all the way to 3180-3208 for the final 3. My final load of 50.6 (.7g above hornady published max) finally showed an ejector mark (3208fps).

Not really looking for information on which different bullet or powder or cartrige, etc that I should be using, but specifically I am looking for:

• Have you ever loaded 139g SST's over H414 for a 7mm-08 and if so - what kind of velocities did you get? EDIT: Or Win760
• Have you loaded a different bullet (especially 139/140s) over H414 for a 7mm-08 and if so, did you see velocities exceeding expectations significantly?
• If you have QuickLoad - what does the software say I "should be getting" and where I "should" be stopping on charge weight?

BTW ... I am using a Caldwall chronograph I purchased used from another member here and have only recently begun to use it ... it is NOT a known quantity for me yet but I have chrono'd a number of rounds from a few different rifles and have not been getting values that would make me think the Chrono is off by 200-300 fps which is about the "surprise" delta I am seeing with my above load combo ...

Would love to hear your personal experiences with H414 in 7mm-08 and/or QuickLoad data ...

Oh ... and if it turns out this data is not too good to be true and is safe and accurate, I think I'll name this rifle "The Unicorn"

Thanks

 

[308win]

I think you have a bad chrono? 7-08, 139gr, 22" barrel does not equal 3200fps!!!!

 

[sierracharlie338]

Can't lend any help on the H414 and 7/08 combo. I used H414 in my Roberts when I first started loading for it but didn't see any strange velocity numbers with that powder.

A word of caution on Quickload. What you see from quick load isn't always what you get. I had a guy run some data for me and the numbers were way off by about 200fps or maybe more. This was after very detailed data input. Never could figure out why

 

[nkyshooter]

I think you have a bad chrono? 7-08, 139gr, 22" barrel does not equal 3200fps!!!!

My first thought too - but - other rifles with known velocity loads in that rifle are clocking pretty accurately. Next step to verifying is to chrono with a different chronograph though for sure ... In the meantime, hoping to hear if others have had similar experiences because I agree these numbers don't make sense unless this rifle really is a "unicorn" ...

 

[308win]

Quickload requires case capacity as a starting point. If you don't know the water weight of the brass you are using, then your just guessing. As with anything reloading, you have to know every parameter before making judgment.

 

[308win]

I would still work up a load watching for the usual pressure signs and then verify later with a good chrono. Who cares how fast it's going if it doesn't shoot? As far as the SST goes, I love that bullet on deer, hogs, coyotes. I run a 130 out of my 270 and everything that gets infront of it drops right there!

 

[nkyshooter]

I would still work up a load watching for the usual pressure signs and then verify later with a good chrono. Who cares how fast it's going if it doesn't shoot? As far as the SST goes, I love that bullet on deer, hogs, coyotes. I run a 130 out of my 270 and everything that gets infront of it drops right there!

That's the plan and agree on the accuracy over velocity approach - however, when I have the option of 2 accuracy nodes, and they are 150fps apart - I want the higher one so my effective range is extended. BUT - not at the expense of safety - ever.



Hoping to hear:

• Have you ever loaded 139g SST's over H414 for a 7mm-08 and if so - what kind of velocities did you get?
• Have you loaded a different bullet (especially 139/140s) over H414 for a 7mm-08 and if so, did you see velocities exceeding expectations significantly?
• If you have QuickLoad - what does the software say I "should be getting" and where I "should" be stopping on charge weight?

 

[Saskquatch6]

I recently got a B&C stock to drop my Savage 7mm-08 sporter into and saw undeveloped handloads move from over 1.5" at 100 to well under an inch (.7-.8ish). Very encouraged with the improvements so now I've begun some true load development for this setup. FYI - always looking to learn more but I'm a very experienced reloader and have experience with reading cases/bolt lift for pressure signs.

I built a ladder charge using the 139 SST's I had on hand (.486 G1 BC) and H414 which I have a good deal of (I know, not ideal for temp stability but has never given me issues personally) ...

I used data from Hornady 11th edition (mobile app) which shows max charge of 49.9g. @ 2900fps

• Hornady FL sized, trimmed, weight sorted all cases weighing within .2gr of one another
• CCI-BR2 primer
• Savage 10
• Savage factory sporter 22" barrel (do not know the twist rate)
• Sunshine, slight breeze, 45 deg F - firing from bench in shade under the roof over the firing line

I started at 46.7 and moved up in increments of .3g. The top 3 or 4 charge weights were definitely compressed some.

I started at the bottom and the chronograph clocked the 46.7, 47.0, 47.3, 47.6, & 47.9g loads between 3000-3050fps. - I wasn't expecting any pressure signs down here since I was starting out a good bit below max (6.5%) but I was NOT expecting velocities near that high. The Hornady 11th ed shows 47 grains should put the velocity somewhere around 2750 fps (with a 24" bbl while mine is just a 22"bbl)

I had loaded the ladder to book max (49.9g according to Hornady 11th) plus a couple more (last/highest at 50.6g), planning to stop when an ejector mark arrived at the party ... No stiff bolt, no marks, no primer craters, etc so I continued and saw velocities increasing all the way to 3180-3208 for the final 3. My final load of 50.6 (.7g above hornady published max) finally showed an ejector mark (3208fps).

Not really looking for information on which different bullet or powder or cartrige, etc that I should be using, but specifically I am looking for:

• Have you ever loaded 139g SST's over H414 for a 7mm-08 and if so - what kind of velocities did you get?
• Have you loaded a different bullet (especially 139/140s) over H414 for a 7mm-08 and if so, did you see velocities exceeding expectations significantly?
• If you have QuickLoad - what does the software say I "should be getting" and where I "should" be stopping on charge weight?

BTW ... I am using a Caldwall chronograph I purchased used from another member here and have only recently begun to use it ... it is NOT a known quantity for me yet but I have chrono'd a number of rounds from a few different rifles and have not been getting values that would make me think the Chrono is off by 200-300 fps which is about the "surprise" delta I am seeing with my above load combo ...

Would love to hear your personal experiences with H414 in 7mm-08 and/or QuickLoad data ...

Oh ... and if it turns out this data is not too good to be true and is safe and accurate, I think I'll name this rifle "The Unicorn"

Thanks

My go to load for 7mm-08 is 47.2 gr H414 - 139 gr Hornady SST or Interbond - 2904 FPS - Rem brass - CCI-BR2 - stock Tikka T3 - 22.3" bbl. Seating was limited by magazine length - CBTO = 2.190" max (jump = 0.093") and average group size = 0.8". I use the SST's for working up loads and smaller game (antelope) and the Interbonds for anything bigger. Took a really nice bull moose (200 yds) with this combo 2 years ago. The H414 powder structure overcomes the compressed load issues of the 4350's but gives same velocity range or better and meters extremely well. This load (47.2 gr) was approaching max and I'm certain the 49.9 gr load mentioned would be unsafe and way over pressure in my rifle. Hope this helps

 

[nkyshooter]

My go to load for 7mm-08 is 47.2 gr H414 - 139 gr Hornady SST or Interbond - 2904 FPS - Rem brass - CCI-BR2 - stock Tikka T3 - 22.3" bbl. Seating was limited by magazine length - CBTO = 2.190" max (jump = 0.093") and average group size = 0.8". I use the SST's for working up loads and smaller game (antelope) and the Interbonds for anything bigger. Took a really nice bull moose with this combo 2 years ago. The H414 powder structure overcomes the compressed load issues of the 4350's but gives same velocity range or better and meters extremely well. This load (47.2 gr) was approaching max and I'm certain the 49.9 gr load mentioned would be unsafe and way over pressure in my rifle. Hope this helps

Hey @Saskquatch6 - that's good info ... and ... that's only about a 125fps or so delta from what I was measuring ... I'm using Hornady brass (prepped and weight sorted) and I intentionally used the heavier cases from my lot so I would be finding pressure sooner by using the smaller internal volume cases ... 125fps is not too much to explain away on potential differences between remington and hornady brass ...

I used COAL vs CBTO and was right around 2.795" which puts the case mouth in the cannelure ... this equates to about .060" jump in my rifle ... I didn't roll crimp but I did put a very slight factory crimp with my Lee factory crimp die just to get improve consistency of neck tension.

I'm hoping there are several folks that have some first hand experience like yours that will chime in and can help validate or repudiate ...

Thanks for that info/feedback

 

[Deans]

I recently got a B&C stock to drop my Savage 7mm-08 sporter into and saw undeveloped handloads move from over 1.5" at 100 to well under an inch (.7-.8ish). Very encouraged with the improvements so now I've begun some true load development for this setup. FYI - always looking to learn more but I'm a very experienced reloader and have experience with reading cases/bolt lift for pressure signs.

I built a ladder charge using the 139 SST's I had on hand (.486 G1 BC) and H414 which I have a good deal of (I know, not ideal for temp stability but has never given me issues personally) ...

I used data from Hornady 11th edition (mobile app) which shows max charge of 49.9g. @ 2900fps

• Hornady FL sized, trimmed, weight sorted all cases weighing within .2gr of one another
• CCI-BR2 primer
• Savage 10
• Savage factory sporter 22" barrel (do not know the twist rate)
• Sunshine, slight breeze, 45 deg F - firing from bench in shade under the roof over the firing line

I started at 46.7 and moved up in increments of .3g. The top 3 or 4 charge weights were definitely compressed some.

I started at the bottom and the chronograph clocked the 46.7, 47.0, 47.3, 47.6, & 47.9g loads between 3000-3050fps. - I wasn't expecting any pressure signs down here since I was starting out a good bit below max (6.5%) but I was NOT expecting velocities near that high. The Hornady 11th ed shows 47 grains should put the velocity somewhere around 2750 fps (with a 24" bbl while mine is just a 22"bbl)

I had loaded the ladder to book max (49.9g according to Hornady 11th) plus a couple more (last/highest at 50.6g), planning to stop when an ejector mark arrived at the party ... No stiff bolt, no marks, no primer craters, etc so I continued and saw velocities increasing all the way to 3180-3208 for the final 3. My final load of 50.6 (.7g above hornady published max) finally showed an ejector mark (3208fps).

Not really looking for information on which different bullet or powder or cartrige, etc that I should be using, but specifically I am looking for:

• Have you ever loaded 139g SST's over H414 for a 7mm-08 and if so - what kind of velocities did you get?
• Have you loaded a different bullet (especially 139/140s) over H414 for a 7mm-08 and if so, did you see velocities exceeding expectations significantly?
• If you have QuickLoad - what does the software say I "should be getting" and where I "should" be stopping on charge weight?

BTW ... I am using a Caldwall chronograph I purchased used from another member here and have only recently begun to use it ... it is NOT a known quantity for me yet but I have chrono'd a number of rounds from a few different rifles and have not been getting values that would make me think the Chrono is off by 200-300 fps which is about the "surprise" delta I am seeing with my above load combo ...

Would love to hear your personal experiences with H414 in 7mm-08 and/or QuickLoad data ...

Oh ... and if it turns out this data is not too good to be true and is safe and accurate, I think I'll name this rifle "The Unicorn"

Thanks

Be careful with H414. My experience it is not temp stable same as W760 (same powder). Had that problem several years ago when working with 140g TTSX. Temps from 40's to 70 avg velocity was 2882. When temps went up velocity increased also.
If you have Varget or Big Game you should not have to be too concerned about temperature fluctuations. There are more powders out there that aren't so temp sensitive I just have experience with those two.

 

[nkyshooter]

Thanks @Deans - I've been using 414 in my 260RemAI for several years ... including in temps up to 90+ F ... while this is not a thread about 414 and it's sensitivity, I do agree that for warmer temp usage, it carries higher risk and therefore the hand loader should target the lower velocity accuracy node.

For a deer rifle that will rarely see usage in temps over 60 let alone up 70 or more, it is much less a concern for me but I will also test again come July/August to ensure I am not inviting a bolt action grenade to the party down the road

Thanks for that velocity with the Barnes ... what kind of 414 (or 760) charge weight and what brass were you using with that 2882 fps?

 

[Deans]

Thanks @Deans - I've been using 414 in my 260RemAI for several years ... including in temps up to 90+ F ... while this is not a thread about 414 and it's sensitivity, I do agree that for warmer temp usage, it carries higher risk and therefore the hand loader should target the lower velocity accuracy node.

For a deer rifle that will rarely see usage in temps over 60 let alone up 70 or more, it is much less a concern for me but I will also test again come July/August to ensure I am not inviting a bolt action grenade to the party down the road

Thanks for that velocity with the Barnes ... what kind of 414 (or 760) charge weight and what brass were you using with that 2882 fps?

47.5g H414. Rem brass

 

[jimbires]

here is a quickload . I changed the COAL to your 2.795" 139sst , H414 , default everything else . you are pushing pressures . I'm guessing a couple cycles on the brass and the primer pockets will be gone . I'll also say your chrony is off a fair amount .


the 7mm-08 is rated at 60191 psi max


Cartridge : 7 mm-08 Rem.
Bullet : .284, 139, Hornady SST InterLock 28202
Useable Case Capaci: 47.817 grain H2O = 3.105 cm³
Cartridge O.A.L. L6: 2.795 inch = 70.99 mm
Barrel Length : 22.0 inch = 558.8 mm
Powder : Hodgdon H414

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-20.0 87 40.48 2421 1808 34993 8512 88.1 1.348
-18.0 89 41.49 2484 1905 37579 8790 89.5 1.307
-16.0 91 42.50 2549 2005 40371 9059 90.8 1.264
-14.0 93 43.52 2613 2108 43385 9318 92.1 1.222
-12.0 96 44.53 2678 2213 46640 9564 93.2 1.182
-10.0 98 45.54 2743 2322 50175 9798 94.3 1.144
-08.0 100 46.55 2808 2433 54002 10016 95.3 1.106 ! Near Maximum !
-06.0 102 47.56 2873 2548 58156 10219 96.2 1.070 ! Near Maximum !
-04.0 104 48.58 2938 2665 62675 10405 97.1 1.036 !DANGEROUS LOAD-DO NOT USE!
-02.0 106 49.59 3004 2785 67598 10573 97.8 1.002 !DANGEROUS LOAD-DO NOT USE!
+00.0 109 50.60 3069 2907 72962 10721 98.4 0.970 !DANGEROUS LOAD-DO NOT USE!
+02.0 111 51.61 3135 3033 78788 10847 98.9 0.939 !DANGEROUS LOAD-DO NOT USE!
+04.0 113 52.62 3200 3161 85155 10952 99.3 0.908 !DANGEROUS LOAD-DO NOT USE!
+06.0 115 53.64 3265 3291 92133 11033 99.7 0.879 !DANGEROUS LOAD-DO NOT USE!
+08.0 117 54.65 3331 3424 99801 11089 99.9 0.851 !DANGEROUS LOAD-DO NOT USE!
+10.0 119 55.66 3396 3559 108254 11119 100.0 0.824 !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 109 50.60 3210 3180 88446 10403 100.0 0.899 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 109 50.60 2875 2552 58550 10461 92.4 1.063 ! Near Maximum !

 

[nkyshooter]

here is a quickload . I changed the COAL to your 2.795" 139sst , H414 , default everything else . you are pushing pressures . I'm guessing a couple cycles on the brass and the primer pockets will be gone . I'll also say your chrony is off a fair amount .


the 7mm-08 is rated at 60191 psi max


Cartridge : 7 mm-08 Rem.
Bullet : .284, 139, Hornady SST InterLock 28202
Useable Case Capaci: 47.817 grain H2O = 3.105 cm³
Cartridge O.A.L. L6: 2.795 inch = 70.99 mm
Barrel Length : 22.0 inch = 558.8 mm
Powder : Hodgdon H414

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-20.0 87 40.48 2421 1808 34993 8512 88.1 1.348
-18.0 89 41.49 2484 1905 37579 8790 89.5 1.307
-16.0 91 42.50 2549 2005 40371 9059 90.8 1.264
-14.0 93 43.52 2613 2108 43385 9318 92.1 1.222
-12.0 96 44.53 2678 2213 46640 9564 93.2 1.182
-10.0 98 45.54 2743 2322 50175 9798 94.3 1.144
-08.0 100 46.55 2808 2433 54002 10016 95.3 1.106 ! Near Maximum !
-06.0 102 47.56 2873 2548 58156 10219 96.2 1.070 ! Near Maximum !
-04.0 104 48.58 2938 2665 62675 10405 97.1 1.036 !DANGEROUS LOAD-DO NOT USE!
-02.0 106 49.59 3004 2785 67598 10573 97.8 1.002 !DANGEROUS LOAD-DO NOT USE!
+00.0 109 50.60 3069 2907 72962 10721 98.4 0.970 !DANGEROUS LOAD-DO NOT USE!
+02.0 111 51.61 3135 3033 78788 10847 98.9 0.939 !DANGEROUS LOAD-DO NOT USE!
+04.0 113 52.62 3200 3161 85155 10952 99.3 0.908 !DANGEROUS LOAD-DO NOT USE!
+06.0 115 53.64 3265 3291 92133 11033 99.7 0.879 !DANGEROUS LOAD-DO NOT USE!
+08.0 117 54.65 3331 3424 99801 11089 99.9 0.851 !DANGEROUS LOAD-DO NOT USE!
+10.0 119 55.66 3396 3559 108254 11119 100.0 0.824 !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 109 50.60 3210 3180 88446 10403 100.0 0.899 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 109 50.60 2875 2552 58550 10461 92.4 1.063 ! Near Maximum !

Thank you for running this...

I am going to try and get the actual h2o capacity for my lot of Hornady brass.

To do this do I fill the case with water to the base of the neck or the mouth of the case at the top of the neck?