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AR15 Bolt Carrier Group Issues

DerBarbarianDerBarbarian Member Posts: 289 ✭✭
edited May 2013 in Ask the Experts
Hey guys I just took my bolt carrier completely apart and cleaned it, but I'm having an issue when I put it back together. I put it back together EXACTLY how I took it apart, but now the firing pin has play in it, about ? of an inch forward/back which I know it shouldn't have any play whatsoever. It sits perfectly until you move the bolt assembly itself when you pull it out it doesn't move on its own but you can pull the back end of the firing pin out the ? of an inch whether the bolt assembly is out or in. When you push the assembly back in, the rear end of the firing pin pushes out by about ? of an inch or so, you can push it forward or pull it back that ? of an inch.I included a couple of pictures to help it explain it better. Sorry if my explanation is a bit confusing, been awake for 36 hours at this point and I haven't infused any caffeine as of yet.


The First picture shows how it should be normally, the second shows how far out you can actually pull the firing pin. I would really appreciate any input you guys might have.

20130528032746.jpg



20130528032809.jpg
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Comments

  • dcs shootersdcs shooters Member Posts: 10,870 ✭✭✭
    edited November -1
    That's normal as the firing pin floats in the bolt.
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  • MobuckMobuck Member Posts: 14,124 ✭✭✭✭
    edited November -1
    Is the FP retainer installed BETWEEN the head of the FP and the guide buttress or in front of the buttress? In other words, can you pull the FP backward out of the bolt as you have it assembled? There is normally 1/4" +/- of travel in a properly functioning FP. If it wasn't moving freely before you cleaned it, it was clogged with grease or fouling.
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  • beantownshootahbeantownshootah Member Posts: 12,776 ✭✭✭
    edited November -1
    Pretty sure the firing pin NEEDS to be able to move, otherwise it won't set off a round when struck!

    Anyway, as mentioned AR-15 firing pins are free-floating, meaning that if they're clean and functioning properly there is SUPPOSED to be about 1/4" back and forth play in them.

    As mentioned, yours was probably resticted a bit by dirt before; now its OK.
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  • DerBarbarianDerBarbarian Member Posts: 289 ✭✭
    edited November -1
    Alrighty, thanks guys I appreciate the input, It's been a while since I've taken it apart so I couldn't remember if it was supposed to do that or not. I really appreciate the input!
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  • Riomouse911Riomouse911 Member Posts: 3,492 ✭✭✭
    edited November -1
    It is all good! [8D]
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  • TxsTxs Member Posts: 17,809 ✭✭✭
    edited November -1
    What you're seeing is part of the AR's design and is perfectly normal.

    You apparently didn't notice, but this movement existed prior to your disassembly.

    EDIT:

    quote:Originally posted by Riomouse911
    As a side note; when you put the bolt together, always take the time to make sure that the firing pin is installed and seated before the retaining pin ("cotter pin") is placed in the bolt to hold it in place.

    This, of course, would not allow the firing pin to move forward, making the gun useless.I agree this simple check during reassembly is VERY important.

    Simply cycling the action with an unsecured firing pin floating around in there can cause it become wedged and jam the carrier tightly within the receiver.

    Disassembly of the upper receiver group may be required to free things up. Damage to the aluminum receiver walls by the much harder firing pin may also occur.
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  • Riomouse911Riomouse911 Member Posts: 3,492 ✭✭✭
    edited November -1
    As a side note; when you put the bolt together, always take the time to make sure that the firing pin is installed and seated before the retaining pin ("cotter pin") is placed in the bolt to hold it in place. On the range I had to look at one a couple of months ago that was put together by the shooter with the retaining pin seated in front of the shoulder on the firing pin. This, of course, would not allow the firing pin to move forward, making the gun useless.

    it's a simple thing, but it does happen.
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