270 Winchester build

Discussion in 'Gunsmithing' started by 270 MKV, Oct 8, 2012.

  1. 270 MKV

    270 MKV Well-Known Member

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    Back in 1995 when stationed in Bremerton, I was looking for a new hunting rifle. The local WalMart had some Weatherby rifles in stock. Looked at the Vanguards I was not too impressed they did not fit me and the bolt was sloppy. Then I saw this Mark V. Hmmm shouldered it…great fit…bolt was firm and cycled without any excessive slop. I place it on layaway (can’t do much on an E-4 salary) and in a couple of months I picked it up. Put a Redfield Partner 3-9x40 on it. Total price was about 670 bucks.
    This rifle has treated me well over the years. It could hold a 1MOA group for about 9 shots. The tenth shot, and the warm barrel would start to let the group grow. I have taken it to 500 and 700 yards (targets only) shooting 130gr Nosler Ballistic Tips. It worked well, with the 24” sporter barrel.
    I had been kicking around the idea of something with some more snort to reach to possibly 1K as one of my buddies has a Sako in .338 Lapua.
    Hmm hard decision on what caliber and make to use!!!
    I was already familiar with the 270 Winchester, and after a brief stint working in Kalifornia I was able to procure a boatload of Winchester Supreme Ballistic Silvertips from Walmart..it was on sale…some goofy new Kalifornia law about leaded ammunition..
    Anyway, I already was outfitted to load for 270 WIN, and had a ton of ammunition for it…then I read the article on this website regarding “re-purposing” a 270 Winchester into a long range rig!!
    Hmmmm well, the action could handle anything (it’s a 9 lug)..I could just go to 300Win Mag…but the idea of a one-off 270 Winchester Build just had a nice ring to it.
    So I called Benchmark, decided to have them re-barrel it with a 27” 1-9 twist with brake…should kick like a 243!!!! Should outpace a 308….should be a hell of a lot of fun!!!
    Ships out today!!! Optic and other stuff sitting in the safe ….just waiting

    Specs:
    Action: 9 lug Weatherby Mark V (US BUILT)
    Chambering: 270 Winchester
    Barrel: Benchmark 27”, 1-9 twist with 5R rifling.
    Stock: coated OEM
    Optic: Nightforce 3.5-15x50 FI (Super-Secret Squirrel Version Mil/Mil, MLR reticle)
    Base : Warne 20MOA
     

    Attached Files:

  2. FEENIX

    FEENIX Well-Known Member

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    Congrats on a very nice rig! That thing is screaming for 165/175 Matrix VLD or the upcoming 170 VLD from Berger. :):Dgun)

    My initial .270 Win handloads as I fireform to AI yielded:

    [FONT=Verdana, Arial, Helvetica]Win Brass, CCI BR-2 Lilja 30" 1:8 barrel 3-groove ,

    165gr Matrix VLD (COAL = 2.674”)

    1) 58.5gr H1000, Vx = 2821 FPS, SD = 20 FPS
    2) 58.5gr H4831SC, Vx = 2981 FPS, SD = 17 FPS

    175gr Matrix VLD (COAL = 2.684”)

    1) 57.5gr H1000, Vx = 2801 FPS, SD = 5 FPS
    2) 57.5gr H4831SC, Vx = 2919 FPS, SD = 16 FPS
    [/FONT][FONT=Verdana, Arial, Helvetica](pix below)

    [​IMG]

    Shows some promise, no pressure signs yet.

    Good luck and happy safe shooting/hunting.


    Ed



    [/FONT]
     

  3. 270 MKV

    270 MKV Well-Known Member

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    That is the plan. Looking at starting loads with 4831sc per my Nosler Book (160gr Partitions)

    I feel like a kid on Christmas Morning...can't wait!!!
     
  4. 270 MKV

    270 MKV Well-Known Member

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    Started putting things together last night. Snapped a few pics with my DumbPhone...not the best quality, but it at least gives an idea of the build.

    Also checked possible max COAL...with bullets .020 off, they will not fit in the mag, nor will a live round eject when it's that long. So, I for the time being, I will just load to mag length. I do have the option to lengthen the bolt slot to allow the bolt to travel further back. I also have the optionto remove the magazine spacer to allow a longer cartrige to fit in the magazine.


    Ran into another potential issue. The original barel had a feed ramp machined into it. This one does not and as such VLD bullets have a tendency to hit the lower part of the barrel and will not chamber. Factory Loads and Similarly loaded Nosler BT and AB loads can also hit, but the tendency is lower.

    I have tweaked the mag spring slightly to put more pressure on the front of the mag follower and less on the back. This has helped some, but it looks like I will have to cut a feed ramp into the barrel in order to make it bullet proof.
     

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  5. 270 MKV

    270 MKV Well-Known Member

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    Well, got it running!!! Lapped in and polished the feed area on the barrel also installed a new mag spring…loads all my dummy rounds without a hiccup!!!

    Got it sighted in with some 130gr Winchester Ballistic Silvertips. Chrono’d them at anywhere from 3011 to 3049…the 3049 was an oddball…most were closer to the 3010 range…so will use that as a reference for these rounds.

    Shown is how the 130gr Winchesters group @ 100 yards…shot from a bipod…good enough for gov’t work IMO.

    Next is to work on the Matrix VLD loads!!
     

    Attached Files:

  6. 270 MKV

    270 MKV Well-Known Member

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    Started plaing with some loads...

    Using H4831 at 56.5 grains, the Matrix 165 VLD are moving at ~2850...used regular large rifle primers.

    Going to try some CCI BR-2 Primers next to see what happens...then tweak the load some to ge a good group.
     
  7. Hired Gun

    Hired Gun Well-Known Member

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    Why not go 270 Weatherby Mag?

    I would be curious to see a picture of what you did to your barrel to get it to feed VLD bullets at home.

    Nosler just announced a nice new 270 Accubond with a better BC than the old ones.
     
  8. 270 MKV

    270 MKV Well-Known Member

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    Why not 270 WBY Mag???

    It does not pass the Wall Mart Test!!!

    Finally got time to test a load for group @ 100 yards...so far so good. Will have to wait till Elk Season is over to try and tighten it up at longer ranges.
     

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  9. 270 MKV

    270 MKV Well-Known Member

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    Basicly, I took a 1/2" hex drive socket and chucked it up in a Lathe...then cut the socket part back to get a 15 degree face cut...essentially made a 15 degree lapping tool.

    Then got a 12" hex drive extension.

    put the whole thing in a variable speed drill, and with the assistance of some valve lapping compound, lapped in a feed ramp...takes a steady hand.

    Once done, I used some Hollywoods polishing compound and a polishing pad to polish it up...

    Looks like new!!!
     
  10. Clark

    Clark Well-Known Member

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    Oct 19, 2006
    I killed 4 mule deer in 2008 and killed 5 in 2009 with a .270 I built.
    Most of the shots were between 400 and 500 yards, shot prone with a 9-13" swivel bipod.
    I was shooting 130 gr Nosler ballistic tips.
    I used a Leica CRF rangefinder and chart made from Quicktarget calculations.
    I shot them broadside aiming for the front 1/3 of the animal.
    Half the deer were bang-flop, and the other half averaged 75 feet of travel.
     
  11. 270 MKV

    270 MKV Well-Known Member

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    Backed out to 200 yards and did a minni ladder test.

    Loads:

    56.3gr 4831sc, AVG=2788, ES=15, SD=8.5

    56.5gr 4831sc, AVG=2802, ES=24, SD=9.3

    56.7gr 4831sc, AVG=2813, ES=23, SD=10.6

    Each test group has 5 rounds.

    The 56.7gr test while statistically the worst, showed the best group. However, it is too hot. It is showing some flattened primers and some gas leakage around one primer. I will have to change powders to make this work any better. Going to try H1000 and see how that works
     

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  12. 270 MKV

    270 MKV Well-Known Member

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    finlly settled a load.

    57.5 grains of H1000, works out to ~ 2840 FPS...
     
  13. FEENIX

    FEENIX Well-Known Member

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    Which bullet did you finally settled with?
     
  14. 270 MKV

    270 MKV Well-Known Member

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    Matrix165