120 gr. TTSX velocity concern

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sure as shootin

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I developed a load for my Sako 85 SS 7-08 this summer using 120 gr TTSX. I tried using RL 15 first but found the accuracy wasn't all that great so I switched to Varget and got a super accurate load at 43.5 grains ,,,,max. with that powder is 43.9 (as suggested by the manual). I worked up a load at that charge but accuracy fell off. I only tested the velocity on a couple of rounds on my 43.5 loads, hoping it would be close to 3000 fps but it was down around 2800 so my concern is will it be fast enough for good expansion using these copper pills?

I know they need at least 2200 fps to open up sufficiently. In all likelyhood, I doubt I'll ever be needing to shoot over 200 yards,,,,the majority of my kills have been half that, or even less for that matter, but it would be nice to know if I'll be good out to 300 yards if i ever need to shoot that far. Do you reckon I'll have enough speed out to that distance for these pills to open up properly? Maybe I need to drop down to 110 gr. TTSX to get that extra velocity but that means going through the whole OCW process again.
 
Your load has more room for improvement.....45gr looks like the max from Nosler and Hornady. Barnes bullets of today can be used with regular data, just watch for the obvious pressure signs.
7mm-08-Rem-120gr.jpg
 
Check with Barnes, every bullet they make have their performance bracket. 2000 fps is a good rule of thumb but some are rated down to 1800 fps.
 
My 120 TSX varget load is going 3050fps out of a 22" barreled 7-08. This is the upper hot node. Sako 85 SS 7-08 with a 20" barrel should loose about 30 fps per inch so 3000 may be achievable with a "hot" load. You cannot use standard bullet loads with mono metal bullets. Going to the Barnes site for their loads found their varget data to be 43.9gr max. My 44gr load shows no extractor swipes or excessively flattened primers. However each barrel is different and that is why you have worked up the load. Ease up and exceed the published max with caution by 0.3gr increments. Make sure you have at least 60 thou jump. My 2c.

Back to your question....I would say go out and kill some dinner with that load you have without worry and maintain your limitation under 250 yards. 99% of your game could be in that zone so go get em. Remember that chronys lie and you may have just had a bad data day. Accuracy trumps velocity any day.
Elky.
 
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https://www.americanrifleman.org/articles/2011/10/17/handloading-lead-free-bullets/
Barnes of today are a little different then the other mono bullets.... they are all copper and have the relief bands cut in them. The article above explains some things.

This is not entirely true with the softer, all-copper bullets from Barnes. The Barnes reloading data generally matches the data for conventional lead-core bullets and in some cases a touch more powder is required to achieve conventional bullet velocities with Barnes Triple Shocks, Tipped Triple Shocks or MRX bullets.
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elkhuntr said:
My 120 TSX varget load is going 3050fps out of a 22" barreled 7-08. This is the upper hot node. Sako 85 SS 7-08 with a 20" barrel should loose about 30 fps per inch so 3000 may be achievable with a "hot" load. You cannot use standard bullet loads with mono metal bullets. Going to the Barnes site for their loads found their varget data to be 43.9gr max. My 44gr load shows no extractor swipes or excessively flattened primers. However each barrel is different and that is why you have worked up the load. Ease up and exceed the published max with caution by 0.3gr increments. Make sure you have at least 60 thou jump. My 2c.
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The barrel of my 85 is 22", not 20. I'm pretty sure I could go up a few tenths in powder higher because I did during the work up but I found that accuracy falls off according to my interpretation of the OCW results,,,,,, the 43.5 looks to be middle ground for the best harmonics of the rifle. I've always believed that accuracy trumps velocity.

Hitzy, I would think that best data to follow for Barnes bullets would be the data that Barnes provides because if anyone knows their bullets, they should. I know every rifle barrel is unique and some xcan exceed the maximum suggested, but as I said, I found accuracy falling off when I exceeded 43.5 grains. You're also looking at Nosler data for a rifle barrel that's 26" long (according to the chart).
 
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sure as shootin said:
The barrel of my 85 is 22", not 20. I'm pretty sure I could go up a few tenths in powder higher because I did during the work up but I found that accuracy falls off according to my interpretation of the OCW results,,,,,, the 43.5 looks to be middle ground for the best harmonics of the rifle. I've always believed that accuracy trumps velocity.

Hitzy, I would think that best data to follow for Barnes bullets would be the data that Barnes provides because if anyone knows their bullets, they should. I know every rifle barrel is unique and some xcan exceed the maximum suggested, but as I said, I found accuracy falling off when I exceeded 43.5 grains.
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Well your initial question was about getting some extra velocity for some expansion buffer room, that's what I addressed. Your chrony confirms you are not overly close to being at max pressure, and have some room to work up...if you want more velocity.
Your chrony is the best tool you have for determining pressure.
 
I emailed barnes about the ttsx and what speeds are needed for expansion. They replied with a min of 2200fps but 2400 and up was better the actually get it to expand. From what I have seen is they seem to call a deformed tip expansion.

This is still expanded according to them. I would disagree

IMG_04148.JPG
 
hometownhero said:
I emailed barnes about the ttsx and what speeds are needed for expansion. They replied with a min of 2200fps but 2400 and up was better the actually get it to expand. From what I have seen is they seem to call a deformed tip expansion.

This is still expanded according to them. I would disagree

IMG_04148.JPG
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HTH, the picture, is that a recovered 120 gr tsx from your 7-08? If yes care to share a bit more on the recipe and performance?

OP, sorry to high jack...trying the tsx is in the back of my mind for this fall.

Best Regards
Ron
 
RonR said:
HTH, the picture, is that a recovered 120 gr tsx from your 7-08? If yes care to share a bit more on the recipe and performance?

OP, sorry to high jack...trying the tsx is in the back of my mind for this fall.

Best Regards
Ron
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It is not. Pulled the pic from on line. That is not what I would call good expansion.
 
RonR said:
HTH, the picture, is that a recovered 120 gr tsx from your 7-08? If yes care to share a bit more on the recipe and performance?

OP, sorry to high jack...trying the tsx is in the back of my mind for this fall.

Best Regards
Ron
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I'm just under a compressed load with this recipe. At 44 gr. I'm compressed so I could probably get another 100 fps if I had to but it's hard to argue with the accuracy I'm getting at 43.5 gr. I'm going to try this load this year and hope that I'll be OK with shots under 300 yards in regards to achieving sufficient expansion. That being said, I can't recall ever having a longer shot than 150-175 yds. but you kind of want to know it will still do the trick at 300 if the need arises.

3 shots at a 100 yds. during my load work up:

 
Hitzy said:
And try and hit shoulder to get some expansion lol
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Thanks for posting the chart! It looks like I should be able to still get sufficient expansion at 300 yards (2205 fps),,,,but I'll make sure I'm trying to hit a shoulder. LOL As I said earlier, though, if my shots at deer are anything like they have been the last few decades they'll be in the hundred yards or even less area. I'm going to do another velocity test his week because I can't recall if it was a sunny day which may have affected the results I got with my "more economical" ProChrono.
 
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