7RUM & Vv N170

Discussion in 'Reloading' started by Freebore, Dec 29, 2011.

  1. Freebore

    Freebore Well-Known Member

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    Anybody using N170 in the 7RUM? I cannot find any data to even start with. I've ran out of Retumbo & 160 Accubonds and have 2# of this 170. I have 162 A-max moly, 168 SMK, 154 SST's, and 175 Spitzers Even QuickLoad data would help. Rifle is a 700LSS stock. Any help much appreciated.
     
  2. brianwinzor

    brianwinzor Well-Known Member

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    I do not own a 7mm RUM so I cannot give you data for that cartridge.

    However, I have used Viht N170 in a 25/06AI, 257Weatherby, and 300 RUM. I have found that my lot of Viht N170 is virtually identical in burning rate in the above cartrideges to AR2225 (H Retumbo in USA)

    In my Rem 700 300 RUM (similar case capacity to 7mm RUM) using Remington Cases, and Federal 215 primer:
    180 grain Nosler BT
    100.0 grains AR 2225 - 3289 (Max)
    100.0 grains Viht N170- 3292 (Max)
    100.0 grains Viht N570 - 3313 Max)

    I suggest that when using Vihtavouri N170 you start about 10 % below your Hodgdon Retumbo maximum loads that you used previously in your 7mm RUM and work up from there.

    Hope that the above is of some help. Regards, Brian
     

  3. Freebore

    Freebore Well-Known Member

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    brianwizor
    Thanks for your data. I do have a 257 Weatherby I can try it in. What bullet/charge are you using in the 257?

    I'll load some of the N170 in the RUM starting where you suggested with the 168's and work up. Retumbo maxes out in the 92/93 range with 160's in my rifle.
     
  4. brianwinzor

    brianwinzor Well-Known Member

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    Sadly I no longer own a 257W, as my .257W, 25-06AI, and .224 Clark were stolen about 2 years ago.

    However, I still have the chrono data that I worked up in my Custom 257W, with REM 700, and Krieger 26 inch 1 in 7 twist barrel. (no freebore)

    Using Norma 257W cases, Federal 215 primer
    Nosler 100 grain BT
    72.0 AR 2225 - 3347 (Mild)
    76.0 AR2225 - 3561 (Max)
    72.0 Viht N570 - 3286 (Mild)
    75.0 Viht N570 - 3607 (Max)
    82.0 H 870 - 3553 (Max)

    I did not try Viht N170 with the 100 grain BT, but as you can see I tried Viht N570 and AR2225 which should give you a clue. I did use Viht N170 with the Wildcat 156 grain ULD.

    Wildcat 156 grain ULD
    64.0 AR2225 - 2831 (Max)
    64.0 Viht N170 - 2841 (Max)
    69.0 H870 - 2881 (Max)
    70.0 AR2218 (H50BMG in US) - 2872 (Max)

    Good Luck, Brian.
     
  5. 7stw

    7stw Well-Known Member

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    Freebore, I have 4pounds of this powder and tried it in my 7RUM. I tried 91 grains and a 140 nosler ct bullet. I did not have have my chronograph at that time, but I don't think the velocity was not that much. Recoil as lite, but the muzzle blast was ferocious! I think it will be useful with heavy bullets, versus lite 140's. I will eventually try some 160's and will revisit it. I am told that if you use Retumbo charge weighs and work up slowly, the results should be OK.I have the powder from a .338 Lapua project a few years ago. It seems to like to be lite with WLRM primers. When I got this rifle, I was hoping to utilize it. Will do more testing. I think it is a usable powder given the case capacity, and the right weight bullet. AIM SMALL,MISS SMALL:)gun) 7STW
     
  6. Freebore

    Freebore Well-Known Member

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    7STW,

    I have an Accumark in 7STW to push those 140s'. I got this RUM 'cause I was the only one the guys knew who was LH when a comrade passed who had one. Talked me right into it. It's a Rem 700LSS and it's a cannon and it takes whole lot of powder.
    Trying to find a good load for this thing with what I have on the shelf just figured somebody might be shooting this VV powder. And I thought the STW case was big! I haven't seen anything that the 7STW won't do really.
    I agree I think the 140 are not the way to go but 160's and upward should work. Planning to go to range in am. Thanks for the reply.
     
  7. 7stw

    7stw Well-Known Member

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    Freebore, what are you shooting in your STW? If you are shooting RL22 or 7828' that stuff stuff works in the rum as well, with 140's, but when you approach 3400' you have to be careful if the weather warms up. I am getting 3406 with 6 fps spread. I am shooting Hornady 140 Interbonds. Powder charge is 88.4, RL22. The 7828 load is the same, velocity is 3360 ish. Just wanted to let you know in case you have these powders on hand. ( assuming you use it in your STW) AIM SMALL, MISS SMALL lightbulbgun) 7STW.
     
  8. Freebore

    Freebore Well-Known Member

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    7STW,

    140 TTSX with Ramshot Magnum pushing envelope at 3450 in my Accumark. 162's run 3150 w/RL-25 it has a brake.

    The last of my 162 A-max's (moly) and last of Retumbo 93.0 grain shot a .257 3 shot group this morning at 100 yrds in my 700LSS, which does not have a brake. I think I'll bed it and get a brake on it now that it looks promising. I like the A-max too.

    I like brakes....with a back that is bolted together and shoulders that are pinned and a chest wired togther things can get screwed-up in a heartbeat and these cannons can hurt.

    Thanks for your load info. I just htink that big frigin' case needs a t least a 160. and those 162 a-max's running 3350 from point should be promising. I'll see if I can find more of those 162 A-max's on the shelf somewhere and try that N-170 out.

    I did try some 154's sptzr's also this morning a 3 1/2" vertical...at 3450.
     
  9. 7stw

    7stw Well-Known Member

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    Whoa, and I thought my arthritis was bad, man I can't even compare to that. I have some 168 Berger VLD's ( orange box), that I know WILL shoot, and I also have some 162 A-Maxes, that I am am also sure that will shoot, but if I can't get her to shoot the 140's, I will load the 160class bullets and maybe turn down the heat a little,( but not to much)!!!! My son smoked a doe last summer on a crop damage hunt at 305 yards and made perfect spine shot. DRT. I have never used A-maxes for hunting, but they do shoot. Those would be the candidate for the n-170, or the 168's. Keep in touch and let me know how you make out. Keep in touch ! AIM SMALL, MISS SMALL lightbulbgun) 7STW.