Switching bolts between M1A rifles?

thefitter

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I know the answer to this in standard bolt rifles but not sure with a M1A rotating bolt.

I'm going to do some trouble shooting tomorrow at the range and trying to isolate a problem by process of elimination.

I plan on switching trigger groups between my Loaded and my Scout. My question is can I swap bolts as well?

Thanks
 

bfoosh006

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    Re: Switching bolts between M1A rifles?

    I don't know for sure...but,I'm not so sure I'd do that...certainly not with that platform/design. Ask the guys on http://m14tfl.com/upload/ you'll have to join, but it is worth it.

    What problems are you having ?
     

    thefitter

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    Re: Switching bolts between M1A rifles?

    Thanks I did post over there. I'm having some FTF, FTE and light strikes.
     

    bfoosh006

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    Re: Switching bolts between M1A rifles?

    What ammo? What brand magazine?
     

    thefitter

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    Re: Switching bolts between M1A rifles?

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bfoosh</div><div class="ubbcode-body">What ammo ? </div></div>

    Federal - American Eagle M1A and GMM 168. Also DAG surplus. All of this runs really well in my Loaded, not 1 problem... but not in my Scout.


    Mags are SA and CMI
     

    bfoosh006

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    Re: Switching bolts between M1A rifles?

    How old is the Scout.. ( approx. round count? ) Has it been cleaned/lubed throughly? A good scrub with the chamber brush? Gas Piston slides freely ?
     

    thefitter

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    Re: Switching bolts between M1A rifles?

    Brand spanking new. Problems right out of the box. Sent it back to SA, they fired 6 rounds and said they can't find any problem. The problems are sporadic.

    I broke down the bolt and found the plunger for the extractor spring in 2 pieces and 1 extra pencil lead size piece of metal I can't id. That would not explain the light strikes though.

    I wanted to take it back out tomorrow and swap some parts and see if I can figure out where the issue is.

    The thing is clean as a whistle so I know it's not gunk in the gas system.

     

    bfoosh006

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    Re: Switching bolts between M1A rifles?

    Does the pencil lead sized piece look like any of the bolt parts? http://www.chestnutridge.com/14pic.asp ...like parts 15,14 ?

    As for the light strikes, it may not be fully going into battery. When you wrote FTF, did you mean "Failure to fire" or "Failure to feed" ?
     

    thefitter

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    Re: Switching bolts between M1A rifles?

    No.

    #14 the ejector and spring are intact. The plunger that goes in the extractor spring #15 was broken. SA is sending me a new one.

    The odd piece is about the size of solid 22 gauge wire maybe 1/8" long. I thought it could be some stray metal piece that got into the bolt during manufacture. That could explain FTE and maybe a FTF but not a light strike. I had 4 light strikes in a row. That's with manually cycling the action, not using gas/recoil.
     

    thefitter

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    Re: Switching bolts between M1A rifles?

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bfoosh</div><div class="ubbcode-body">Does the pencil lead sized piece look like any of the bolt parts? http://www.chestnutridge.com/14pic.asp ...like parts 15,14 ?

    As for the light strikes, it may not be fully going into battery. When you wrote FTF, did you mean "Failure to fire" or "Failure to feed" ? </div></div>

    I had 1 failure to feed the rest (12+)were failure to fire.
     

    thefitter

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    Re: Switching bolts between M1A rifles?

    Now that I think about it it could be a small piece of spring.
     

    bfoosh006

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    Re: Switching bolts between M1A rifles?

    Clean the chamber with a chamber brush throughly, I can't help but wonder if it isn't fully locking the lugs ( thus ingaging the firing pin with the receiver "safety" bridge...) FTE, dirty chamber or gas piston/gas cylinder/pluged gas port.

    Found the "Safety Bridge" Link... http://m14tfl.com/upload/showthread.php?t=83837
     

    thefitter

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    Re: Switching bolts between M1A rifles?

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bfoosh</div><div class="ubbcode-body">Clean the chamber with a chamber brush throughly, I can't help but wonder if it isn't fully locking the lugs ( thus ingaging the firing pin with the receiver "safety" bridge...) FTE, dirty chamber or gas piston/gas cylinder/pluged gas port. </div></div>

    I tried that this week. I let a sopping wet bore mop soaked in Hoppes sit in the chamber for 30 minutes and then scrubbed thoroughly. Then I cleaned the gas system, receiver and broke down the bolt. Greased and oiled everything up. I'm taking it back out tommorow. We'll see what happens!
     

    bfoosh006

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    Re: Switching bolts between M1A rifles?

    Well... keep us posted, nice talkin' with ya. Time for the sack, little woman keeps sneakin out and giving me the stink eye look and that come to bed look.
    Enjoy your rifles, BTW I bought the SAI M21...that rifle can friggin' shoot. I can tell when I don't "breath right" at the moment of trigger pull, it shows up on the target. ( My favorite rifle..)
     

    Badshot308

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    Re: Switching bolts between M1A rifles?

    Make sure you look at the position of the bolt and that it's cammed fully into battery. If it isn't fully in battery and the gun fires in spite of the receiver safety bridge, you could have a very nasty out of battery detonation.
     

    samnev

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    Re: Switching bolts between M1A rifles?

    I wouldn't swap out bolts unless I first checked it with a go and no go gauge first. I'd go to a local gun shop and ask them to check the head space on the new bolt. They probably would do it at minimal or no cost if your a regular customer. You would probaly be ok but why take a chance.
     

    Jerry m

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    Re: Switching bolts between M1A rifles?

    No, bolts are not 100% interchangeable without checking headspace.

    Good luck

    Jerry
     

    thefitter

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    Re: Switching bolts between M1A rifles?

    Took the Scout that's giving me trouble along with my loaded to the range Friday, here's what happened:

    1) Shot 40 rounds through the loaded using all the same mags and the same ammo with no problems.
    2) Swapped the Scouts trigger group into the loaded and shot 40 more rounds no problems.
    3) Put the Scout trigger group back into the Scout and replaced the scouts broken extractor spring with the one from the loaded and had a failure to fire on the first try. Pushed on the op rod and bolt was all the way forward. Cycled that round out and fired the next 2 rounds no problem.
    4) Next round also FTFire, cycled by hand and finished the mag no problems.
    5) Put the loaded trigger group into the Scout and ran through 2.5 mags no problem.
    6) At this point I thought maybe it had worked it's self out but on the next mag the 2nd rounds spent case was stuck in the chamber. I had to push the op rod on the edge of the bench to get it to extract. The rest of that mag went ok.
    7) Put the Scout trigger group back into the Scout and ran a full mag with no issues.
    8) Next mag round 2 was a light strike, cycled by hand, light strike, cycled by hand fired the next 2 OK, then light strike again.
    9) At this point I had had it with the Scout and was going to put the extractor spring back into the loaded and finish off 2 more mags. I discovered that the scout had some how broken the extractor plunger again, just like it had on it's own extractor spring.

    Overall the day sucked but I did learn a little bit more this time out. I know it's not the mags, ammo or trigger. I know it's not a cleanliness or lubrication issue. And I know that something about this scout breaks extractor plungers. But that does not explain the stuck cases or the light strikes. Every time I had a light strike the trigger made a funny click, twang, rattle sound.
     

    81Z4ME

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    Re: Switching bolts between M1A rifles?

    I wouldn't just swap bolts. That may create a headspace issue or even if the headspace is okay you may not have good contact on both both bolt lugs with the receiver.

    Are you sure the bolt is going all the way into lockup every time? I've seen other rifles (not M1A's) with the bolt almost, but not quite, fully forward/locked up and when the hammer falls the round will not go off but the hammer will sometimes "knock" the bolt into the fully locked up position (sometimes not, and you can see that right away). If your rifle is breaking the extractor pin/spring maybe the extractor is striking the barrel when the bolt closes (this could cause the bolt not to fully lock up every time and could cause the extractor to move enough to put the pin/spring in a bind when the bolt is forced fully closed. Is there a wear pattern developing on the outside edges of the extractor?

    Before I swapped bolts I'd swap the extractor first and then the firing pin.

    Good luck with it.
     

    former naval person

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    Re: Switching bolts between M1A rifles?

    You may have slightly long chamber. That would explain the light strikes. If the primer fires and the powder burns, the case base will abruptly back out, hit the bolt face and look reasonably normal. (Maybe a little flattening on the primers.) I had that happen with a .35 Whelen...the factory new brass was minimum and the chamber maximum. I had to expand to .375 and resize to form a "false shoulder" that would hold the case back against the face of the bolt. After the first firing, the cases fit well and no problems with misfires after that. Get the headspace checked and check your ammo with a headspace gauge too. JMHO
     

    samnev

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    Re: Switching bolts between M1A rifles?

    Since you have done exhaustive research on the problem I would send it back to SA agin detailing everything that you have done. I talked to the supervisor of the repair department before I sent mine back the 2nd time and he got things fixed after the first tech gave me the story nothing was wrong.
     

    Top Cat

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    Re: Switching bolts between M1A rifles?

    I think you have some minor problems, and it sounds like you may be able to fix them on your own.

    First of all...you can't just swap bolts. They are an armorer hard-fit item. You can have the headspace checked, but I have not seen h/s to be a problem in Springfields. They are built to commercial specs, and military rifles are longer and fire fine. It's a possibility, but you can eliminate the other potential issues first.

    Disassemble the bolt and clean the interior of the bolt thoroughly with a brush. Let it soak overnight if necessary to get all the gunk out. When clean, check the firing pin protrusion from the bolt face in the Scout bolt and compare it with the one in the Loaded model...I don't remember the spec off hand. Just a little debris in the nose section of the bolt can restrict firing pin protrusion. You can also compare the two firing pins while you have them apart. If the Scout is shorter, ask SA for a new GI firing pin.

    Clean and compare the two trigger groups. You may need a new hammer spring, or there may be some other defect in the Scout trigger group causing a weak strike. It's hard to give comprehensive advice on this, but check for burrs and make sure it is clean and greased/lubed properly. You can ask SA for a new hammer spring either way.

    The extractor problem is likely caused by an out-of-spec aftermarket extractor. This is a very common issue. Ask Springfield to send you a GI extractor, pin and spring for the Scout, and replacements for the Loaded model.

    When you have exhausted your efforts, you can always send it back to SA with detailed description of the problem after first talking to a supervisor as Santo describes. Make it clear you want the rifle thoroughly inspected and fixed...just taking a rifle out of the box and firing a few rounds to see if it goes bang is not trouble shooting a problem.

    TC