XCR break-in questions (issues?): (1) light strikes and (2) POI vs. POA
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Thread: XCR break-in questions (issues?): (1) light strikes and (2) POI vs. POA

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    Newbie poochee's Avatar
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    XCR break-in questions (issues?): (1) light strikes and (2) POI vs. POA

    New XCR owner and really like it. However, after 400+ rounds, I'm getting light strikes...with all brands (Federal, PMC, Privi Part. ..all 55 gr). In today's outing, I had 6 of 80 rounds not firing (at least 1 of each brand). The attached photo shows the more pronounced dimple in the round that fired and the smaller one for the light strike. With almost 500 rounds, I'm expecting better by now. Advice?

    Also (and forgive the ignorance of 5.56/.223 ballistic traits). My rounds keep rising depending on the distance to target. My shooting is confined to a 150' indoor range, which may not be a fair distance to draw conclusions, but the POI rises from 50' to 100' and again to 150' (in each case the POA is the middle if the black dot...I had zeroed at 100'). As above, this happens with Fed, PMC and PP, but the spread varies. Is it normal for the POI to keep rising like this?

    Thanks in advance for your responses.
    Attached Thumbnails Attached Thumbnails XCR break-in questions (issues?): (1) light strikes and (2) POI vs. POA-dsc_0009a-standard-e-mail-view.jpg   XCR break-in questions (issues?): (1) light strikes and (2) POI vs. POA-dsc_0010a-standard-e-mail-view.jpg   XCR break-in questions (issues?): (1) light strikes and (2) POI vs. POA-dsc_0011a-standard-e-mail-view.jpg   XCR break-in questions (issues?): (1) light strikes and (2) POI vs. POA-dsc_0012a-standard-e-mail-view.jpg  

  2. #2
    XCR Guru variablebinary's Avatar
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    Re: XCR break-in questions (issues?): (1) light strikes and (2) POI vs. POA

    Quote Originally Posted by poochee View Post
    New XCR owner and really like it. However, after 400+ rounds, I'm getting light strikes...with all brands (Federal, PMC, Privi Part. ..all 55 gr). In today's outing, I had 6 of 80 rounds not firing (at least 1 of each brand). The attached photo shows the more pronounced dimple in the round that fired and the smaller one for the light strike. With almost 500 rounds, I'm expecting better by now. Advice?

    Also (and forgive the ignorance of 5.56/.223 ballistic traits). My rounds keep rising depending on the distance to target. My shooting is confined to a 150' indoor range, which may not be a fair distance to draw conclusions, but the POI rises from 50' to 100' and again to 150' (in each case the POA is the middle if the black dot...I had zeroed at 100'). As above, this happens with Fed, PMC and PP, but the spread varies. Is it normal for the POI to keep rising like this?

    Thanks in advance for your responses.


    Speaking broadly from my target experiance, and I am by no means a great shooter or "Snipa", but POI and POA are only identical at two points of a bullet arch. Everything inbetween requires some degree of calcuation for maximum precision.

    The barrel of a gun is not straight, when zero'ed. If so the bullet would begin dropping as soon as it left the barrel and you'd be striking low at anything over 50 yards. You have to angle the barrel slightly up, hence, rising POI compared to POA the farther you move from the barrel. However, the bullet will eventually start to drop and eventually POI/POA will be the same again for a brief moment.

    It's up to the shooter to know the bullet path and know at which point POI and POA are the same. Generally speaking, a 16" barreled XCR zero'ed at 50 yards will have identical POI and POA at 50 yards and 200 yards. You're going to have to compensate for shots inbetween.
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    XCR Guru TerraShrewsbury's Avatar
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    Re: XCR break-in questions (issues?): (1) light strikes and (2) POI vs. POA

    To verify, you have the 5.56 model?

    Have you had any trigger work done to the rifle, either by yourself or someone else?
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    Newbie poochee's Avatar
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    Re: XCR break-in questions (issues?): (1) light strikes and (2) POI vs. POA

    variablebinary - good tutorial, thank you. I assume that the practical answer to my question is that "yes, it climbs in the early feet from the muzzle (including within the first 150')." I'll note with respect that my outstanding Arsenal 7.62x39 does not demonstrate anywhere near the same climb differential (anticpiating a "mass-of-bullet" reply). I suppose I was expecting a simpler "it's normal, stupid, don't worry about it" response.

    Tarra - VERY responsive, as per your normal monitoring of this Forum. Yes, it's a 5.56N and no trigger work has been done whatsoever...straight from the factory in late June. This is one awesome rifle and I plan to post a photo soon of my tweaking; but I need to resolve this reliability question (spoiled with an AK that's been zero-defect for over 4K rounds).

    This is a great forum.

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    XCR Guru TerraShrewsbury's Avatar
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    Re: XCR break-in questions (issues?): (1) light strikes and (2) POI vs. POA

    Well, we can fix this two ways. I can have it sent in for inspection or you can quick-fix it and have a heavy hammer put in instead. Let me know what you would like to do.
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    XCR Guru dont_tread_on_me's Avatar
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    Re: XCR break-in questions (issues?): (1) light strikes and (2) POI vs. POA

    For the light hammer strikes you could try bending the hammer spring just a bit.If you remove the hammer via the pin it rides on,Take the spring off the hammer ,you will notice the spring has a shallow v shape.Take the spring and try to make that v more shallow.This should make the spring stronger.You may just have gotten a weak hammer spring.

    VB as usual very good info.I would add that with a hundred yard zero,with the 55 grain load with a velocity of 3250 fps ,then your maximum rise point should be at about 180 yards,with a maximum point blank range of 357 yards.This is assuming a 5 inch kill zone.



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  8. #7
    Jack A Sol
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    Re: XCR break-in questions (issues?): (1) light strikes and (2) POI vs. POA

    Just to verify, but you have gone thru the gun and cleaned and checked and locktited all the bolts since break in was completed right? also make sure your barrel bolt is torqued in pretty good as well.

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    Newbie poochee's Avatar
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    Re: XCR break-in questions (issues?): (1) light strikes and (2) POI vs. POA

    Cleaned & lubricated thoroughly after every trip to the range, yes. Have inspected bolts but not detected a need to use Locktite (for the example, the infamous ejector seems as tight as day one). Barrell bolt did loosen slightly, but detected and corrected previously.

  10. #9
    Jack A Sol
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    Re: XCR break-in questions (issues?): (1) light strikes and (2) POI vs. POA

    good man 8)

    send her in and have them check her out. :2cents:

  11. #10
    Expert magikbullet's Avatar
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    Re: XCR break-in questions (issues?): (1) light strikes and (2) POI vs. POA

    zero your rifle for 50 yards-it gives the most usable trajectory. buis on the xcr start with a 3" poa/poi difference at the muzzle rather than a 2.6" difference of an ar, but the 50yard zero is still best.



    this is for a 16" barrel w 55g amax from an xcr.

    here is the difference for the 50y zero between ar and xcr:


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