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Thread: Sierra Gamechanger OAL

  1. #1
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    Sierra Gamechanger OAL


    Anyone messed with the new Gamechangers? I ordered some 168gr for .308 and 90gr in .243. Measuring the OAL on these I am finding it's like stupid long: 3.02" in the .308 and 2.887" in my .243

    Loading them to saami will have them jumping a river and loading them 20 thou off the lands does not have much bearing area in the neck...

    So before I go messing with them and wasting my time and $$$$, has anyone else already played with them?

  2. #2
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    I shoot TMKs in .308 and .223 and found that loading them out results in better accuracy than seating them at the Sierra recommended 2.800 and 2.260 respectively.
    I seat them out so the jump is the same as for the SMKs.
    With the .308, the Savage mags are deep enough to handle the extra length.
    With the .223 69 and 77 grain TMKs, that makes them too long for the AR magazines on my Les Baer so I shoot them with a single round follower.
    With those two calibers, the TMKs are at the top of my best load lists with multiple powders.
    For two .308 rifles, the top 25 loads for both rifles are with 155, 168, 175 and 195 TMKs exclusively, but one of the rifles prefers heavy bullets and the other prefers lighter bullets.
    The Les Baer includes 8 loads with TMKs out of the top 25 loads (7 of the 8 are 77 TMKs) with 5 of the top 10 loads being TMKs.

    The ogive on both caliber TMKs are about in the same positions as the ogives on the equivalent weight SMKs but the TMKs are at least 0.08 longer because of the tips.
    Yet Sierra recommends seating them back so the O.A.L. is the same as the SMKs.

    I asked Sierra if they recommended the shorter O.A.L. to accommodate the AR shooters magazines and the tech that I talked to (via their chat line) admitted that that was the case, especially for the .223 69 and 77 grain TMKs.

  3. #3
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    I currently shoot 77gr TMKs in my .223 Wylde Savage 12. I am loading them to a very long 2.45" to be 20 thou off the lands and they shoot great. In my AR-15 (another .223 Wylde) they would have to jump .150 at max magazine length. I am not sure I would ever even bother trying it...

    The GameChangers look to be another 15-35 thou longer than even the TMKs. Guess I will try them really long in the bolts actions and see what happens.

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    I noticed this as well. I'm at the lands in a brand new custom 243 barrel at 2.850" give or take a thou due to tip variance. I'm going to load them at 2.8 and see what happens. I think it's just going to have to jump or go on down the road.

    Sent from my SM-G960U using Tapatalk

  5. #5
    Team Savage Stumpkiller's Avatar
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    I have some in 0.264" (130 gr) and I load them in my .260 Rem for a 0.015" jump using 2.875" c.o.l. That's 0.075" longer than SAAMI. (But 0.015" shorter than my hunting load with the 143 Gr Hornady ELD-X I seat to 2.890")

    I'm still working with powder type & amount and then I'll change that jump.

    Still playing, though. These may be what I hunt with next fall.
    "They couldn't hit an elephant at this distance." Last words of Gen. Sedgwik

  6. #6
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    I just hit order on some last night for my 270. I'll be interested to see how they do. Im hoping I'm not bumbing the edge of the magazine when I seat them out

  7. #7
    Basic Member Bigbuckdn's Avatar
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    I just ordered some in 284 to try in custom 284 that I am currently building on short action
    I have 2.995 to play with or I can always single load it and back it up with game kings
    depending on POI
    Old Smokey

  8. #8
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    Might find a load that shoots well jumping.

    The 308 bullet is long tho! I think i read its 1.409”? My berger elite hunter 180 grain has better ballistic coeff and is 1.375” and shoots well jumping

  9. #9
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    Quote Originally Posted by Orr89rocz View Post
    Might find a load that shoots well jumping.

    The 308 bullet is long tho! I think i read its 1.409”? My berger elite hunter 180 grain has better ballistic coeff and is 1.375” and shoots well jumping
    You know, if it weren't that I was such a "very proper type guy", I could have lots of fun with some of these obviously very serious comments. lol

  10. #10
    New Member Boogieman's Avatar
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    Loaded some last night for my 11VT 308. Using Sierra's data with Varget, and loading them out to 2.880 (.020 off lands). Waiting on a new scope to go try them out.

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