Page 1 of 2 12 LastLast
Results 1 to 10 of 11

Thread: Shooting a 7mm Rem Mag thro a .308 moderator ?

  1. #1

    Shooting a 7mm Rem Mag thro a .308 moderator ?

    Hi

    Re the title. Since i've used the mod on the 7mm Rem Mag it's not been grouping as well. Havent had time or ammo to try it without the mod since i've got it back from being screwcut. Is anyone aware of any probs caused firing a smaller (albeit only .62 mm smaller ) bullet through the larger moderator.
    Comments gratefully received

    Scrun

  2. #2
    Scrun

    Both the 260 and 243 in my gallery are used with a .30 cal AU-SL5 mod and I am happy with the accuracy. Apart from going to proof, they aren't fired without the moderator on. Some questions for you:

    What type of mod? Screwed on the end or over the barrel?
    Which specific model?
    Are you using factory ammo or your own home loads? If you are using home loads, then I would work up a new load for the rifle + mod.

    A later thought - have all the actions screws, mounts etc been checked for tightness?

    Good luck. JCS
    Last edited by jcampbellsmith; 22-10-2011 at 18:25. Reason: anything loose added

  3. #3
    Two possible explanations. How bad is bad? Previous good loads may need re-adjusted with the mod.

    The other issue is the crown. The rifle should really be re-crowned after threading, even if it was not shortened. Made that mistake in the past.
    Brian.

    Just because you are paranoid, doesn't mean they aren't out to get you......

  4. #4
    hi mate.i switch my s5 mod between a t3v in 25-06 and a tikka 695 continental master in 30-06 and i dont have any probs,18/1 thread on mine.

  5. #5
    Quote Originally Posted by swarovski View Post
    hi mate.i switch my s5 mod between a t3v in 25-06 and a tikka 695 continental master in 30-06 and i dont have any probs,18/1 thread on mine.
    Hi all,

    Likewise I use my .30 cal S5 on both my t3 243 and my Remmington 700 in 7mm Rem Mag with no probems whatsoever accuracy in the 7mm rm is possibly better (this may be due to barrel harmonics) but I suspect that the sound reduction efficiency on the 243 is not a good as it may be had I opted for the closer matched hole for this calibre.

    Cheers Remmy7

  6. #6
    I wouldnt say the moderator is the problem....I regularly advise people to buy one mod in the biggest caliber they intend to shoot unless they have enough money not to worry about it. Yes, you loose a little of the effectiveness but in truth its hard to actually tell and even a .22 c/f is moderated through a .30 cal 'can'.
    Check the crown / accuracy without the mod. When the mod is fitted the rifle crown is to a degree then at the end of the mod anyway. It may well be a new load or make of ammo will suit better or it may be the additional weight of the mod causing stock problems.
    You have a lot of fiddeling about to do before you get to the answer but work through things logically.

  7. #7
    Quote Originally Posted by jcampbellsmith View Post
    Scrun

    Both the 260 and 243 in my gallery are used with a .30 cal AU-SL5 mod and I am happy with the accuracy. Apart from going to proof, they aren't fired without the moderator on. Some questions for you:

    What type of mod? Screwed on the end or over the barrel?
    Which specific model?
    Are you using factory ammo or your own home loads? If you are using home loads, then I would work up a new load for the rifle + mod.

    A later thought - have all the actions screws, mounts etc been checked for tightness?

    Good luck. JCS
    Hi
    JCS - it's a Wildcat Predator 8 - screwed over barrel. I'm loading my own rounds - oh dear Looks like i've got some experimenting to do

    Thanks to all for their help and advice - appreciated

  8. #8
    i have one mod for use on 5 calibres.
    the largest is 243 (6mm) the bore is 6.5mm. the smallest is .17
    works fine

  9. #9
    Hi,
    If you load your own, its likely that you adjusted the loads in your rifle to gain optimum accuracy in the first instant, prior to having the moderator fitted. Having a moderator fitted, especially an overbarrel one with a tight fitting bush will most likely alter the barrel harmonics (vibrations).
    My first action would be to adjust the powder by .1 or .2 grain increments up and down .5 of a grain or so either side of your original loading, to see if you can see any improvement, thereafter the seating depth.

  10. #10
    Sounds like you need to conduct load development again. The addition of the mod will adjusst barrel harmonics.

    I certainly noticed a difference in my groups when I forgot my mod on the range whilst using rounds developed a mod.

Similar Threads

  1. For Sale Rem 700, 7mm Rem Mag
    By jordang in forum Firearms
    Replies: 14
    Last Post: 07-09-2011, 14:23
  2. For Sale Sako 75 6mm PPC and Rem 700 7mm Rem Mag
    By jordang in forum Firearms
    Replies: 2
    Last Post: 30-03-2011, 10:41
  3. For Sale 7mm rem mag
    By jb7x57 in forum Firearms
    Replies: 2
    Last Post: 09-03-2011, 14:04
  4. For Sale Rem 700 XCR 7mm Rem Mag
    By jon2 in forum Firearms
    Replies: 6
    Last Post: 04-12-2010, 21:41
  5. 7mm rem mag
    By josh in forum Ammunition, Reloading & Ballistics
    Replies: 8
    Last Post: 18-10-2009, 23:39

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •