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Posted: 2/17/2003 12:33:52 PM EDT
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I have a Rock River Varmint rifle. Last time I was at the range, I feed a round, round did not fire and I could not eject the case. I tapped the charging handle with a rubber mallet and ejected the round. There was a primer strike. Today I shot Black Hills 75 grain no problem. Shot a 3/8th inch group at 100 yards benched. Switched to 68 grain and the first round jammed in. Could not extract. Rubber mallet time again. No primer strike. What is going on? Thanks, David |
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Meanoldman, What brand of ammo is the 62gr that you are having problems with chambering? The first round that had a light primer strike was due to the round not fully chambering and the bolt was not total locked in battery. The second jam that you had was the same as the first. Chances are that you have a tight chamber and the 62gr rounds are either not sized correctly, or are a slightly larger design, such as wolf ammo. Also, this is no need for the use of a rubber mallet. Just grab the cocking handle and pull down while given the butt of the rifle a good blow on the grass. Remember to keep the muzzle pointed up and controlled at all times (don't put anything in front of the muzzle in case you have a discharge). Dano |
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There is a headspace problem of some sort. either with the ammo or the rifle. I would not continue to shoot it until you have your headspace checked. Ditto on what dano said about clearing a stuck round. Just tug on the charging handle and give the rifle a smart rap on the deck (barrel straight up) |
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Thanks for the responses, The 68 grain was Black Hills also. I like your method for clearing the rifle better than mine. I will probably shoot a few more rounds through it. Should I use the foward assist to seat these rounds if they don't completely seat? Thanks, David |
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For God's sake, [b]NO![/b] Jam that round in there and you'll force the bullet hard up against the lands in the barrel. When the firing pin hits the primer, you'll blow up your rifle and possibly maim yourself and anyone unlucky enough to be near you. The rifle is trying to tell you there's a problem. "Firing another couple rounds" isn't going to fix anything...and may well f*ck something...and/or some[i]one[/i] up big time. |
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Meanoldman, You have to remember that "Over all length" of a round bear no relativity when you start to use different types of bullets, The bullet will engage the rifling due to the bullet tip's octave design (side walls) and not the general length of rounds. You started off by stating a 62-grain round, then changed it to 68gr. El_Roto has given you the best advice anyone can give you. The 68 black hills round (bullet octave side walls) is engaging the rifling in your short throated barrel, and is causing the bullet tip to bind. A bullet that is engaging the rifling of loading will cause higher working pressure due to the amount of force needed to release the bound bullet from the rifling. Add that you must shove the round even farther into the chamber means that now the bullet has been driven back into the case and caused the case to have less working volume. These two factors have just caused your 50,000 psi ammo to be well over 60,000 psi. Bottom line is the black hill ammo was re-loaded for a rifle that had a longer throat (end of chamber cut to start of rifling) than your barrel, should not be used in your rifle. Dano |
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Meanoldman, Should be fine, just don't force in any rounds. The one thing that you may want to do is smoke the bullets(tips, not casing) with a Sharpie marker and load the rounds in the chamber by hand to prevent the marker smoking to be disturbed. Look for signs of the bullet making contact with the rifling by the smoking being worn off in straight lines at the end of the octave. Also, when you pull the round out of the chamber, there will be one long line due the tip being dragged on the extension lugs by the ejector/extractor. It is normal and to be expected. Dano |
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