GAS OPERATED OR BOLT ACTION 308

Discussion in 'Firearms' started by irayone, Sep 26, 2011.


  1. irayone

    irayone Monkey+

    I am shopping for a new 308...The M1A or the Remington Scout
    Help me out here....

    1. Will I be more accurate with the M1A being gas operated, longer barrell
    2. The scout is bolt action so a lot more recoil, and 16 inch barrell. I am a weak shooter ( I need all the help i can get) Will the recoil hinder my performance?
    3. Never seen a scope on an M1A????
    4. M1A = 1800.00/ scout = 900.00
    Any thoughts......
     
  2. ghrit

    ghrit Bad company Administrator Founding Member

    I guess that I (for one) can't give you any good advice without knowing what your intended use might be. Hunting? Bolt action, hands down. Zombie defense? M1A takes the prize. Accuracy is another question entirely, both can be MOA with the right fodder.

    Yes, you can scope an M1A. A longer barrel is also useful if you are shooting over irons; other than that, you'll see little benefit from length these days. YMMV, and so others MMV on my opinions.
     
  3. RightHand

    RightHand Been There, Done That RIP 4/15/21 Moderator Moderator Emeritus Founding Member

    If you decide on the M1A and want to scope it, let me know - that's what we do. I can set you up with a complete optics package, scope, mount, rings, cheek riser, plus extras if you want, at prices that will be extremely competitive.

    M14/M1A manufactured for the commercial market do not always strictly adhere to USGI specification in several areas that affect scope mounting and that can cause some problem which Sadlak Industries has been able to overcome. On occasion, the receivers left side groove might be machined either too shallow or two narrow preventing the key on the back of scope mounts from making full contact between the receiver face and mount back. Full contact between these two points is a critical feature in a stable, reliable mounting system designed the the 3-point design. the 3-point design features a counter-acting mounting point for every force applied by the recoil.

    Another area that we have seen is the geometry between the (stripper clip guide) dovetail and the receiver's threaded hole used for the mounting bolt.

    These are all problem that can be overcome.

    Let me know if you have any questions, either by PM or send me an email at sales@sadlak.com and I can help you out at the right price.

    Check our website for more details http://sadlak.com/si_rifle_parts_main.html
     
  4. irayone

    irayone Monkey+

    Thanks for the heads up!!!! Intended use is to get to 800 /1000 yards I am around 400 yards at this time. Any suggestions on recoil with the scout and M1A?
     
  5. RightHand

    RightHand Been There, Done That RIP 4/15/21 Moderator Moderator Emeritus Founding Member

    Remember, mass helps absorb recoil. I think the recoil on both would be similar but I don't have the specs on the comparison. We have several customers successfully shooting to 1000 yds so don't listen to the nay sayers who will tell you it's impossible but the ones I have spoken with are shooting the longer barrel. Remember, who's pulling the trigger is usually more important than the what you have added to the M14. There are other good mounting systems out there, not just Sadlak, but I happen to think we're the best. Check around.

    The M14 has range and take down power so it would get my vote (unless I was tramping though the woods all day with one outfitted with a Sage stock, bipod package, and every available add on - that would kill me. Weight is definitely a factor
     
  6. Opinionated

    Opinionated Monkey+


    I'm about 99.9998% in agreement with Ghrit.

    That last little fraction is way out on the far end. I'm also working my way out to the 800-1000 and found - for me - that barrel length does make a difference. That dagum 7.62 (M1A, .308 bolt gun) is dropping like the proverbial brick at that range. Getting that little (we are talking what 100-200 FPS for every 2" of barrel beyond 18"?) bit of extra zoom on the bullet means it flies just a little flatter just a little farther.

    And, I'm sure ghrit will agree, once you see a ten inch circle at 1000 yards you realize that every little bit helps.

    Psychologically if nothing else. :oops:


    As for recoil . . . .

    it is my opinion that perceived recoil is greater with the bolt gun. But I'd just about be willing to bet that if you rested the stocks on load cells and measured them both being fired the "pounds of force" would be very darned close to the same.
     
  7. happyhunter42

    happyhunter42 Monkey+++

    I own a Rem. model 600 in .308 with an 18" barrel and a scoped weight of about 8.5#. I have never had to fire it pass 500 yds., but I don't think you would have any trouble with a scout at that range.
     
  8. ghrit

    ghrit Bad company Administrator Founding Member

    Yup, perception is the name of the game. Measured at butt, you'll find with your load cell that the recoil impulse energy is essentially the same between bolt or semiauto but spread longer over time. Softer, perhaps, is a better way to describe it; a forceful push vs. a hammer blow. The energy lost in gas bleed is recovered and simply delayed until the action hits the rear stops. (I think.)

    Stock configuration has a lot to do with felt recoil as well.

    I get that Ray's concern is with developing a flinch, possibly from little experience with hard kickers. That's a whole 'nuther subject that MUST be dealt with. [dunno] Somewhat tongue in cheek, if that is so, getting a Moisen Nagant and a box of 200+ gr ammo, going to the range and firing off half a box will reveal all. After that, any 308 will be a piece of cake.
     
  9. Tikka

    Tikka Monkey+++

    The trick is if the bullet leaves the barrel at supersonic speeds then it needs to be supersonic at the target.
    There are three speeds supersonic, transonic and subsonic. When a projectile drops below the speed of sound it goes transonic. It will lose stability at the transonic wall and wobble. The wobble opens group size. The wobble will continue to worsen until the bullet tumbles.
    Velocity is very important when shooting long distances.

    Recoil: Recoil Calculator
     
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  10. Opinionated

    Opinionated Monkey+


    Tikka, this isn't a "gotcha" it's a "maybe I'm not as smart as I think I am" on my part . .

    Isn't supersonic any speed greater than the speed of sound, subsonic any speed less than the speed of sound, and transonic is actually a term for the transition between supersonic and subsonic . . and the other way around - from subsonic to supersonic?

    I guess I asking if transonic isn't actually a transitional state as opposed to a measurable "speed" . . . ??
     
  11. Tikka

    Tikka Monkey+++

    You didn't get me; although I work with aerodynamics types etc I'm not one. :D

    The simple answer is a question: what happens if the speed is maintained exactly transonic or where the projectile wobbles?

    NASA defines transonic as a range of speed: "The first of the rocket-powered research aircraft, the X-1 (originally designated the XS-1), was a bullet-shaped airplane that was built by the Bell Aircraft Company for the U.S. Air Force and the NACA. The mission of the X-1 was to investigate the transonic speed range (speeds from just below to just above the speed of sound) and, if possible, to break the "sound barrier."
    NASA - NASA Dryden Fact Sheet - Research Airplane Program

    Also they test aircraft at transonic speeds in wind tunnels. ;)

    It is thought of as a speed because there is a variance; the wall is where wobble or vibrations are produced.

    Did that help?
     
  12. CATO

    CATO Monkey+++

    I don't think you can view the speed of sound like the speed of light (an integer value that is constant). Given that atmospheric conditions have an impact on the SoS, the actual number (x) will vary and may not be a precise point on the integer scale. And, always recall that between any two integers, either x-y or x+y, there is an infinite number of rational numbers (fractions). Perhaps this "infinity" range is where trans-sonic takes place. [dunno]
     
  13. Opinionated

    Opinionated Monkey+

    Woh. That actually makes sense. :eek:

    Thanks, Tikka! (y)


     
  14. Clyde

    Clyde Jet Set Tourer Administrator Founding Member

    Recall Bernoulli's equation for the pressure in a fluid …

    P1 + ρgh1 + ½ρv12 = P2 + ρgh2 + ½ρv12

    The first term on each side of the equation is the part of the pressure that comes from outside the fluid. Typically, this refers to atmospheric pressure weighing down on the surface of a liquid. The second term is the gravitational contribution to pressure. This is what causes buoyancy (also not relevant right now). The third term is the kinetic or dynamic contribution to pressure — the part related to flow . This will help us understand the origin of pressure drag.

    Start with the definition of pressure as force per area. Solve it for force .

    P = F/A ⇒ F = PA

    Replace the generic force symbol F with the more specific symbol R for drag. (You can also use D if you wish.) Drop in Bernoulli's equation for the pressure in a moving fluid …

    F = PA = (½QV²)A

    Rearrange things a bit and here you go …

    R = ½qCAv²

    And the big C = the drag coefficient.

    Now...what is important is that we keep in mind the small disturbance equation of transsonic flight in light of the the aforementioned equations:

    When the full potential equation is simplified by assuming that perturbation velocities are small and we relate the local speed of sound to the freestream value by making use of the isentropic relations we obtain the small disturbance equation (Equation 1 Below.(derivation).

    When we let the freestream Mach number go to one and ignore the last term, the equation becomes the classic transonic small disturbance equation (Equation 2 Below).

    A great deal has been written about this nonlinear equation and its variants. It is used less frequently these days since finite difference methods can be used to solve the full potential equation directly.

    Well, that is about it for the day. I have used up my time and it's must be beer:30 somewhere!

    [kneelsuckers]
    Equation 1- Small distrubance Equation. Equation 2 -Classic_Transonic_smalldistrubance_Equation.
     
  15. Clyde

    Clyde Jet Set Tourer Administrator Founding Member

    [imwithstupid1]Previous Post Disclaimer:

    TThe aforewritten post by Clyde was meant for purely entertainment purposes. The poster has no formal math or physics training, but believes he can sound like he does. The purpose of this post was to see if by trolling the internet I could actually sound like I knew what I was posting. In the end, for the casual observer I would say I accomplished this because I had too much coffee to get my mind moving and it really is too early in the morning to drink beer, even for me. The earliest I have actually had a beer in the morning (5:30 am) was when I was in Germany - Munich, 1989, when I exited a train and had a bratwurst, potato salad, and a .5 liter beer (ok, I had 2) since milk doesn't go well with that meal. i did actually have a beer at 6:00 am one time, but that was after an entire evening out so it counted not as a first beer of the morning, but the last beer of the night. Speaking of sausauge: I did just buy a meat grinder so I can play around with grinding my own stuff from the book I bought a while back. If you are still reading this then you are stupid because I am about to go into a diatribe about something totally unrelated to this post so that, for purely entertainment purposes, I can continue to sound as if I know what I am talking about on the internet. Note to Posters: if you put up math equations, I will have fun messing with the math equations because that is for math people. Do you prefer Ritter Sport or Milka chocolate? I think we are having smoked turkey for Thanksgiving

    :oops: I think I need to get a few more cups of coffee so I can actually think about thinking about working.
     
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  16. -06

    -06 Monkey+++

    Now that all that is out of the way--if you are going to fire consistant groups at distant targets I would recomend a heavy barreled bolt. I can fire very effectively with my M1A(with iron sights) to about 500 yds. 4" groups offhand at 100 yds. Am no longer into distance accuracy unless I pick up another 700(or similiar shooter). The heavy barrel flexes less, heats up more slowly, and lessens recoil. I still have two bull barreled small caliber shooters that I can pluck a crow's eyelash with at 100 yds. Staying supersonic will definately give you better groups and that is the name of the game.
     
  17. -06

    -06 Monkey+++

    Righthand, sent you a PM. Need advice/help mounting a lever lock scope mount on my M1A. The old eyes need help-thanks.
     
  18. Clyde

    Clyde Jet Set Tourer Administrator Founding Member


    I hear a bingo!(y)
     
  19. Tikka

    Tikka Monkey+++

    In a very simplistic form; past that it gets deep quickly. I asked one of the aero engineers and transonic is between .8 and 1.2 mach.

    To me, accurate long distance shooting requires staying supersonic to target. That's based on the one less thing philosophy.. ;)
     
  20. BTPost

    BTPost Stumpy Old Fart,Deadman Walking, Snow Monkey Moderator

    And if the projectile goes Subsonic, you can hear, and feel, it coming for a few Microseconds, depending on it's speed. If it is supersonic it gets there before the sound and pressure wave does..... Poof Your gone...... ......
     
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