GTA
PCP - HPA - C02 Gate => QB-7X Gate -W/Co2 & HPA => : TML2107 October 19, 2007, 02:27:11 PM
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ok guys i have a quick question. Got a MM QB78D in .22 today and im very happy with it. I wish the temperature was above 64 with wind less than 20mph but hey thats life. Ok so heres the question... i was shooting at walnuts and was able to recover a pellet that lodged itself in the cardboard box i was using as a stand and noticed it had very prominent grooves. like rifling grooves. i thought it was jsut the walnut doing it but im just throwin the possibility that the pellet may have been crushed in the barrel.... (Ramjet pellets by the way...) anyone had this happen in a QB and is this even likely?
Thanks,
Tim
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Not real sure what you are asking...rifling marks are more visible when pellets are a little larger in diameter (and those may be) than when thepellet is smaller...doesn't take much, like .0015-.002", to mae a distinct visible difference.
Generally, if the rifling marks are very deep, it's a sign the pellets are a little large for the barrel. Usually, the skirt shows deeper marks than the head of the pellet, so if accuracy is good and the head isn't shwoing dep engravment, I'd just keep on using them.
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hmm yeah thats not it.. ill have to take a picture and see if its visible in the photo. it was almost as if the pellet was crushed when fired and rotated in its mangled state through the barrel.
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Fill a 5 gallon bucket with water and fire a pellet into it, shouldn't deform to much and look at it again, should have rifleing marks on any surface that touches the barrel.
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Would the marks happen to look similar to these???:
http://i210.photobucket.com/albums/bb9/StevieLaner7777/PICT1111.jpg
If so you've got the same problem as I had awhile back!!
Stevie
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no it was like the pellet was folded into itself before it left the barrel and rotated through. it was probably just the walnut doing everything but it was just weird. my dad lost the pellet and he was the one who was worried. i havent had any problems since as far as i know.
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I would look through the barrel with pin light at the breech end. You may be able to see a defect in the bore. That looks like maybe a bad barrel at one end or the other. Should not have marks that deep on the head of pellet. Best thing to do also is put a pellet in the barrel and use a wooden dowel to push it through. You should only get fine rifleing marks on the skirt and if pellet is real tight maybe some on the outer side of pellet head. That is how I check for rifling uniformity.
Gene
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I would say that since you haven't noticed any more problems, it was a soft pellet and a hard walnut, that did it. Unless you were also shootin a .177 and picked up the wrong cal by mistake, it happens. I don't think Mike would let one out the door with a barrel that bad.
Mike
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nah im sure its fine. its really cooling off and gettin windier than all get out here in ohio. i took a squirrel with a decent shot to the head and whatnot so im doin alright with the rifle. it does what i need it to do. havent had a real chance to really check the accuracy but it seems like as i put more pellets through it gets more accurate. just like mike said it takes a tin or 2 to break the barrel in.