Callahan speedlock upgrade

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Tikkamike, May 21, 2012.

  1. Tikkamike

    Tikkamike Well-Known Member

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    I have what used to by a 700 LSS in 375 rum, I put a Timney in it, extended magazine box, and a CSR brake then dropped it in a B&C Medalist stock. The rifle shoots pretty good but the Ugly J lock was bugging me so I got online and ordered a Bolt Tool and Callahan Speedlock firing pin assembly. Initially I was a little disgusted because the shroud required a little fitting to allow the bolt down the raceway smoothly but it was fairly mild, just a little time and sand paper then steel wool to shine it back up. once I finally had the proper fitment I dry fired a couple times and could already tell a huge difference in vibration. Last night I finally got a chance to go shoot at the range. First I dry fired a few times and the crosshairs had zero movement which was certainly different because this rifle had a ton of vibration before in anything less than a perfect rest. Then I decided to shoot a couple groups. This is where I was very impressed, it cut my groups from the .6-.7 range to the .3-.4 range. I can honestly say this was one of the best $50 I have spend on an upgrade for a 700.
     

  2. Trickymissfit

    Trickymissfit Well-Known Member

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    I have a Tubbs in my 700, and it works pretty good. Lock time is noticebly faster. But I have a lingering thought in the back of my head about it. I got the feeling that it hits the primer so hard that it might be moving the case in the chamber (I know I can't prove it). I use the alloy firing pin, and a spring that looks like it came out of a race hemi. Would like to try a lighter spring weight sometime. The one for sure plus I saw from it was a much more consistent ignition. I also put one in a Savage 112, and really saw improvement, with a locktime at least as fast as the short action Remington with a speed lock kit (maybe faster). But as I said I still wonder if hitting the case that hard is moving the case, plus I also kinda worry about the firing pin bouncing on the primer.
    gary
     

  3. Tikkamike

    Tikkamike Well-Known Member

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    My thought was actually the opposite, yes its faster but its half the weight... will it hit it hard enough with the lack of weight to give good ignition in all temperatures? I guess time will tell as I plan to use this rifle a lot this year here in wyoming some days will be 80* some will be in the -'s, if I have any problems ill be sure to post. but so far im very happy
     
  4. Trickymissfit

    Trickymissfit Well-Known Member

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    well there's nothing scientific about my thoughts for sure. Just lingering thoughts.The ignition with the Remington did seem a little more consistent, but what I was seeking was a reduction in group size. I couldn't prove it helped, but also couldn't prove otherwise. I installed it prior to all the trigger problems I went thru with that Remington, so there's no accurate base to form an opinion over. But where I did see some improvement in was when I shot off hand. The groups seemed better all the time.
    gary
     
  5. rscott5028

    rscott5028 Well-Known Member

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    According to BartB, any firing pin will move the cartridge forward in the chamber and a weak firing pin is the worst as it won't adequately center the round with the angled shoulder firmly against the front of the chamber.

    Not sure if I agree or disagree. And, perhaps I'm misinterpreting his statements... you might go back and check his recent thread about centering in the chamber.

    --richard
     
  6. Trickymissfit

    Trickymissfit Well-Known Member

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    I'm more or less worried about a double or multi strike by the firing pin bounching on the primer face. I didn't install one on my Mod. 12 Savage because folks that knew advised me not to. But It was my brain storm to try it in the 112, plus a Win. 70 and the Remington. Saw the biggest difference in the Winchester with the Remington right in there as well. As for moving the case forward, he's right. How much can be debated till the end of time (our numbers are different). What I liked most was the faster lock time in the Remington because I tend to shoot the rifle off hand most of the time (I hunt coyotes with it about 80% of the time). I see nothing wrong with the idea, but how much it helps I'm not positive. So maybe it just helps me mentally
    gary
     
  7. Tikkamike

    Tikkamike Well-Known Member

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    I neck size only and only partially move the shoulder back when necessary because I like my shells in the chamber tight and centered. Which leads me to believe my firing pin doesnt move my case at all in the chamber.. any knowledge on this? I had never considered this theory before.
     
  8. Browninglover1

    Browninglover1 Well-Known Member

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    If your shell stayed fully conformed to the chamber after firing it would be almost impossible to eject. The elasticity of brass allows it to shrink (extremely small amount) so that the shell can be ejected. Neck sizing will prevent the shoulder from being set back even further, but the cartridge will still move just a miniscule amount when the firing pin hits it until it fully contacts the shoulder of your chamber and the primer ignites.

    For all practical purposes your shell doesn't move much, but theoretically it is still moving just a bit until it firmly seats against the chamber and the primer is ignited.
     
  9. Tikkamike

    Tikkamike Well-Known Member

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    that seems right, although my bolts are all fairly stiff to close... the purpose of that is to center the round in the chamber obviously so if all is square and centered I guess theoretically it wont matter if the firing pic moves my case a little...
     
  10. Browninglover1

    Browninglover1 Well-Known Member

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    I totally agree. The theory behind a lot of things doesn't really matter for practical purposes. Your rifles seem to shoot well enough that whatever your doing is working :)
     
  11. Tikkamike

    Tikkamike Well-Known Member

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    I like to think so, but there is always room for improvement, i wish i had the money to have an action with a barrel screwed to it with windows cut in it so I could better visualize what happens in the chamber. would be fun to experiment with