Quantcast

7Mag Barnes TTSX-140

Discussion in 'Handloading and Reloading' started by Covelo-NdN, Jun 10, 2017.

Thread Status:
Not open for further replies.
  1. Covelo-NdN

    Covelo-NdN Member

    Joined:
    Dec 25, 2014
    Messages:
    71
    Location:
    Ukiah CA
    IMG_2005.JPG Hello the highroad, I've been working on some reloads for the seven mag I put together I'd like to share my results, ask for an opinion and share my enjoyment.

    I live in California we're very soon lead core bullets will be outlawed. I'm going to shoot Barnes. So here's where I'm at so far. I bought the 140 and 150 grain TTSX rounds for the seven mag. I wanted to shoot it a heavier bullet but the 140s do better than the 150s.

    The image attached is a 140 ttsx chronographed at 2842 fps using h4831sc @ 3.240 COAL.
    The cold bore shot was the bullseye. Then it opened up. So here is what I'm wanting to know.

    Should I be happy with this speed? 2842 fps?
    Should I be happy with this bullet weight?

    The answer to my own question is probably yes but I'm seeking for opinions I guess. The reason why I like the H4831sc is because I reload that for the 30-06, and the 270 Winchester. So sticking with that powder is just easier for me I've tried are all R22 with pretty decent results. But that means buying a new powder.

    I think what that's me kind of wondering about this bullet & powder choice is that these numbers really aren't too far off from a 270 Winchester yet this is a 7 mm magnum should not be going faster with a heavier weight?

    I imagine that this seven mag with this set up will have a better trajectory then a 270.

    So would you be happy with the results here? with this speed, with this weight, I mean after all it is a hunting rifle and I think it's a pretty decent group? I'm really limited TV all copper bullets here in California?
     
  2. climbnjump

    climbnjump Member

    Joined:
    Aug 8, 2008
    Messages:
    674
    Location:
    Upper Midwest
    Well, with the same bullet, you won't have better trajectory than a .270 Win if you don't shoot faster than a .270 Win. At 2842 fps with that bullet, you are a bit on the slow side. But to answer your question as to whether or not you should be happy with that load, well, that is a subjective question that only you can answer!

    As to your question about the 7MM RM moving heavier bullets faster, I shoot the 168gr Berger VLD Hunters at 2940 fps and that's not particularly fast. I don't shoot Barnes in my 7mm, but have used them in other calibers with good results, both accuracy and "put-'em-down" results.

    You didn't mention what your intended game and/or ranges are, so it's hard to know if you might want to try to load faster or just be happy with what you have.
     
    LoonWulf and horsey300 like this.
  3. horsey300

    horsey300 Member

    Joined:
    Sep 3, 2016
    Messages:
    2,616
    Location:
    Wyobraska
    Well my friend I gotta ask, what are you hunting at what distances? Have you run coppers on game before? Why are you not putting more rounds downrange per group? Personally, I shoot everything cold dirty bore because that's the most repeatable groups I'll produce on game. The hottest bore would be MAYBE two quick follow ups simulating wounded game scenarios but then always a cool down period. Run 20 rounds downrange. That doesn't look like a BAD group.

    Those numbers are not much more mesmerizing than a .270, did you look into the other powders discussed in your previous thread? I don't believe that velocity trumps accuracy but I like having both.

    Next, I don't think your 7rm needs a 140 copper to take anything short of a Kodiak on this continent, the coppers are a different ballgame. Normally for larger muley bucks I recommend 85 copper, partition, or 90+ bonded/btip/cup and core in a .243. Copper penetrates better, as far as terminal performance, nosler illustrated impact velocities quite nicely with their etip page: https://www.nosler.com/e-tip-lead-free-bullet/
    I would like to note that compared to the .338 gmx and various Barnes bullets, the etip cavity is more generous. Based on the graphic provided, my minimum requirements of impact velocity for big game would be 2400-2600 fps, for varmints I require 16-1800 fps. I don't run a 7rm, I have the stw and various other cartridges of different calibers, primarily the .224 6mm 7mm and .308 diameter, (whilst moving everything but the stw into the .22, .250AI, 6mm, 6.5mm, .35rem or .30-30 category), so you'll have to weigh in with others, but honestly, I'd try the Rl19 work up under the 140 for a target mv of 3000-3300. If you're open to other weights, for California deer or small bear I'd run the 110 or 120 ttsx personally. In a 7 Mag I'd even run that 120 on elk if I could hold an accurate shot. Just thoughts, hopefully someone else can chime in. I know @LoonWulf has a 7rm but idk if he's played with coppers....
    ETA, what range is that group?
     
    Last edited: Jun 11, 2017
    LoonWulf likes this.
  4. LoonWulf
    • Contributing Member

    LoonWulf Contributing Member

    Joined:
    Jul 3, 2010
    Messages:
    12,291
    Location:
    Hawaii
    Ive never used monos in my 7s, either the RM or the STW.
    I personally would be looking at getting those 140s over 3k. At 2850 youve got expansion out to 400-500yds, but how much im not sure.
    The thing about monos is they are ment to be run lite and driven fast. I would honestly drop to 120s and try for 3400-3500ish, if you can get them to shoot well.

    If your shooting stuff bigger than say large deer, you might want to run the 140s. I would still try get the most velocity you can.


    Whats your charge weight on your 140 loads QL thinks you should be able to get 3100+ within limits. Other powders like rl22 would get you another 100fps or so.

    The 120s should break 3300 with h4831sc....again this is all in theory.


    My current load is either a 168Amax/berger/160Tsmk at 3100, havent had anything take a boiler room hit and walk away.
    While these loads arnt legal in cali, you might want to work up a heavier cup n core, or bonded round for long range else where, if you hunt elsewhere that is. They give you a bit more of a velocity/expansion window at longer range.


    Speaking of expanding window, the group you posted looks a adequate to for use out to where youll have issues with expansion and the ttsx, and that velocity.

    One note from running them in a couple other calibers, Ive found they really dont like copper fouling. Ive had groups open up after 20rnds in one particular barrel.
     
    Last edited: Jun 11, 2017
    horsey300 likes this.
  5. jmr40

    jmr40 Member

    Joined:
    May 26, 2007
    Messages:
    13,974
    Location:
    Georgia
    I've heard the expression that a 7 mag is just a loud 270 for years. With the best loads 270 has always been pretty close. The 7 mag shoots bullets about 10 gr heavier than 270 to the same speeds and always has.

    The general rule with copper bullets is to drop down at least 1 or maybe 2 bullet weights compared to conventional lead bullets. Shooting 140 gr copper bullets is going to be comparable to 175 gr lead. I'd drop down to 120, or even 110 gr bullets for deer or bear size game. The 140 or 150 gr copper might be a better option for moose or large bear.

    You should be able to get 3000-3100 fps with 140's. A 270 will shoot 130's to the same speed. But I'd be looking at 110's at 3400 fps or 120's at 3500 fps.

    http://barnesbullets.com/files/2016/03/7mmRemingtonMagnumV10ForWeb.pdf

    Barnes bullets like speed and need at least 2000 fps at impact in order to expand. And most users report 2200 fps is better. Less speed at impact and they act like FMJ, don't expand and will wound rather than kill. The one disadvantage of copper is as a long range bullet. Many lead bullets still expand down to 1600-1800 fps and work better at long range. But when impact speed is enough to give good expansion even the lightest copper bullets give very deep penetration.

    Lead bullets lose weight and come apart at impact. It takes a very tough conventional bullet to retain 80% of it's weight and most are in the 50% or less range. A 140 gr lead bullet that retains 80% of its weight will weigh about 112 gr after impact and give similar penetration compared to a 110 gr copper bullet that still weighs 110 gr after impact.

    I borrowed these graphics from Noslers website showing the difference in bonded bullets vs copper at various speeds. This is for Noslers copper bullet, but the Barnes copper will show similar expansion. Top is their Accubond, bottom is copper.

    [​IMG]
    [​IMG]
     
    LoonWulf, Covelo-NdN and horsey300 like this.
  6. Leatherstocking

    Leatherstocking Member

    Joined:
    Sep 3, 2012
    Messages:
    52
    I've shot lots of whitetails with the 150TSX from a 7Rem Mag, from 50-250 yds. I've been using the Barnes min load of 54grns of IMR 4831.
    All DRT, except one, where I missed the boiler room. Deer took a step just as I pulled the trigger. He went 50 yds.
    Never recovered a bullet, ever.
    I shot these at jugs full of water, and every one looked just like Barnes photos, with 100% weight retention.
     
    Last edited: Jun 11, 2017
    LoonWulf, Covelo-NdN and horsey300 like this.
  7. Covelo-NdN

    Covelo-NdN Member

    Joined:
    Dec 25, 2014
    Messages:
    71
    Location:
    Ukiah CA
    Thanks everyone! Truly appreciate it.

    1. I hunt blacktail deer in Ca. Distances 0-500 in distances.

    2. Never ran copper bullets (accubond have been a favorite for years)

    3. That range for the group posted was 100 yards.

    Conclusion: I'm going to order 120 ttsx along with 168 Berger & 160 accubond.

    California goes full lead ban on 7/1/2019 so I have some time to build up a copper round. I love accubonds. Never shot Berger but hear awesome stuff.

    Thanks guys I hope to push those 120 ttsx as fast - accurate as I can.

    Accubonds: I seen them killl and absolutely love how they anchor game.

    Berger: I hear the shot pin holes and make shot placement steady..
     
    LoonWulf and horsey300 like this.
  8. horsey300

    horsey300 Member

    Joined:
    Sep 3, 2016
    Messages:
    2,616
    Location:
    Wyobraska
    With your 120, you might get a good use outta your Rl22 ;). ETA, with the 120 moving at 3420 (speculation based on Rl22 loads with a bit subtracted for real world applications) impact velocity at 500 yds should be 2182. I wish you the best of luck, keep us posted!
     
    Last edited: Jun 11, 2017
    Covelo-NdN likes this.
  9. Covelo-NdN

    Covelo-NdN Member

    Joined:
    Dec 25, 2014
    Messages:
    71
    Location:
    Ukiah CA
    Thanks very detailed and much appreciated!
     
  10. Leatherstocking

    Leatherstocking Member

    Joined:
    Sep 3, 2012
    Messages:
    52
    Horsey, how do you calculate the velocity at 500 yds.
    Something to do with the BC and muzzle velocity I presume. I don't see any tables in the Barnes manual that help.
     
    horsey300 likes this.
  11. horsey300

    horsey300 Member

    Joined:
    Sep 3, 2016
    Messages:
    2,616
    Location:
    Wyobraska
    You need the bc, mv, sometimes barometric pressure, altitude, temperatures, and bullet weight. The atmosphere conditions I usually leave at default when researching new bullets/loads, but will alter them for field testing. Then just plug them in to a ballistic calculator. I have an app on my phone but there are several online. For my thr calculations, I usually use the hornady calculator as my app only has so much room for various cartridges. My app is strelok, LOADS of fun tools there, hornady calculator can be found here:
    http://m.hornady.com/ballistics-resource/ballistics-calculator
    There are plenty of calculators available, and I don't swear that these are THE BEST but they work well.
    ETA, the calculators will also tell you energy at muzzle and distance, trajectory elevation, and windage.
     
    Last edited: Jun 12, 2017
    LoonWulf and Leatherstocking like this.
  12. Leatherstocking

    Leatherstocking Member

    Joined:
    Sep 3, 2012
    Messages:
    52
    Thanks, I'll check it out.
    Also wondering where the 2000-2200 fps velocity required for expansion of copper bullets comes from.
     
  13. horsey300

    horsey300 Member

    Joined:
    Sep 3, 2016
    Messages:
    2,616
    Location:
    Wyobraska
    Scroll up and look at the images provided from the nosler website via @jmr40. You'll get the absolute minimum expansion at 1800, but they're barely better than a fmj at that point. I run em on furbearers much farther out than big game because of this. The monometals are not a jacketed bullet like traditional cup and core or even partition and bonded bullets. They are one solid chunk of copper/gilding metal alloy with a hollow cavity and either HP or polymer tip, thus activating expansion is not as easy as peeling a thin alloy/copper jacket. You're forcing preformed splits in the entire shaft of the bullet to peel back into petals rather than smashing soft lead into the traditional mushroomed look.
     
  14. Leatherstocking

    Leatherstocking Member

    Joined:
    Sep 3, 2012
    Messages:
    52
    Thanks, again. I looked at my load, 150 TSX, 2700 fps, looks like I have a bit over 2000 fps at 300 yds.
     
    horsey300 likes this.
  15. horsey300

    horsey300 Member

    Joined:
    Sep 3, 2016
    Messages:
    2,616
    Location:
    Wyobraska
    Which is plenty reasonable, while I can and do take long shots on a variety of critters, I can usually get under 400 yds on every large game animal I've gone after. The varmints are another tale for another day ;).
     
Thread Status:
Not open for further replies.
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice