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Discussion Starter · #1 ·
Man I wish I could post a picture! This is going to be a little hard to explain. I was working with my two 35 rem guns. I was working up a couple of different loads. The 336 carbine got a 200 grain remington bullet and the 336A got the 180 grain speer. I was shooting 2 rounds and letting each gun cool as I shot the other. Well, I had worked the 336A up to the recommended max load I got from 35Remington. I had some others that needed shot up so I whaled away offhand about 6-7 rounds. Got the barrel plenty hot. Decided to see what it would do with a hot barrel. At 100 yards I shot 5 rounds that measured one half inch center to center off sand bags. Boy, I thought, this is going to be great! I let the gun cool for 15 minutes. In fact it was quite cool. Then I shot it again. That group was more like 3 1/2". What the !#$&! A friend said that it was a straightened barrel and it went back to its true alignment when heated up. I ain't got much hair left to pull out but this one may get it all by the time I figure it out. Maybe the deer will let me shoot off a half a dozen rounds before I pop one at them. One guy said getting it kryo-ed was not that expensive any more. Anybody done that ? What do you think, Rick
P.S. I'll mail this target to anybody who can add it to this post. Thanks
 

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Have you tried loosning or tightning barrel bands? If they are not to the rifle's liking, a vibration will cause eratic patterns.

SS
 

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Discussion Starter · #3 ·
This was the 336A with the 24" barrel, no barrel bands. Going out right now to shoot some more. Temp is kind of chilly today, 52 degrees, so it won't take quite as long to get a cool barrel to keep trying. Later, Rick
 

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With a hot bbl, first the inside heats up then the rest of the bbl, when the first part starts, the bore actually gets smaller this is why we try not to shoot multiple rounds that heat a bbl, and the reason that cold shot will not be with the rest of the group. After the bbl fully heats up then the bore is back to normal size, albeit that expanded metal does have to go somewhere. All of the attached parts, dovetails holding sights, forearm, tube magazine all react to the equation. To lessen this we try to keep the bbl cool while load testing. Now take in the other things we do, we go out in the woods with a recently cleaned bbl, and expect that first shot to be right where we zeroed. Lot of things that can go wrong. Now back to basics, that 3.5 inch group is actually a good group for a levergun, in fact a bragging group. Figuring deer sized targets, the heart is larger than that. Just to put 3.5 inches in perspective lay three quarters and a dime down that is 3.5 inches. Now think about the size of a deers heart, it is larger than 3.5 X3.5 or a common file card folded in half. The most important thing you can do is to center this group and know it's size. Check the same load at 50 and 75yds this will be your average shot not 100yds. Getting back to your groups, Have you had a trigger job? If not, do so it will help all the way around. If you have a gunsmith do this have your rifles bbl recrowned, though it may look perfect check it anyway. Sometimes this is a problem overlooked. Another thing that needs to be checked is your self. Do this put an empty in your rifle, concentrate on an aimpoint at 25yds on sand bags leave both eyes open while squeezing the trigger concentrate on keeping the crosshairs on the bullseye, after the shot. While this seems strange to do, it is very important to total accuracy. Often times we will do little things at the last moment that throw us off, very minute but still the same. If you are left or right of the target, you may be flexing your pectoral muscles when firing. If you are up or down you may be releasing your grip or tightening it. This is why you should shoot through the target not only with a bullet but your aimpoint. By shoot through I mean aim through also, or keep you sights on the target after the shot. Without recoil these movements can be detected. So while you shot a 1/2 inch group and a 3.5 inch group with the same rifle all your concentration to get that 3.5 inch was not as relaxed as the 1/2 inch group you were not expecting. Tensing at the wrong time has done it to me a quite a few times, and I call this your compeditors best ally. This was a little thing I lived by for many years during my benchrest days. My best ally was my compeditors that beat me, because they will tell you anything if you but ask. Soon they ask the questions. You are doing the right thing by asking, and will get many answers all well intended and mayhaps you'll find an answer. I do hope I have helped. A gun that is capable of a 1/2 inch group will shoot more than one. Get your mechanics aligned and then work on the equations.
 

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One thing I was disappointed with when I bought my A was the fore end was just a little loose.

Some time after 1948 the front sight had been changed to a finer bead and it had been drilled and tapped for a scope mount. After shooting it I realized that who ever thought enough about that gun to improve its sighting capability might have done that on purpose. It may just be shrinkage of an old stock but I can't find any stock to barrel rubs anywhere so some old boy may have relieved it to stabilize groups across a range of barrel temps.

I had a Remington pump that was very sensitive to slide position at fireing for best groups. A little twist the wrong way and well it could drive you nuts....
 

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Discussion Starter · #6 ·
Just got back from the range. Much better lighting today. I definitely appreciate all the help. I was mostly working up loads for my 336-35 rem. 20" carbine today. I had a problem the other day with a double cross-hair showing up just as I was ready to shoot. The horizontal line would double and I had to back off and start again sometimes. Bad light and glasses I guess. Both scopes were crystal clear today. The 336A was right on at 1 1/2" high and fps was running 2279-2286 out of a cold barrel. Both shots were within less than 3/4". So, I'M probably the problem. I had shot 52 rounds the other day. I really got to get a good bench rest setup as the sand bags I use still allow me to wiggle quite a bit. And, yes my triggers are lousy! I've been asking if anybody has a digital gauge but, no luck yet. I may have to buy one at Midway and start to work on them. [winter project] The 20" 336 velocity variation may deserve its' own thread. Thanks, Rick
 

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What the other guys said.

Also, you might consider that your rifle's potential really isn't a half inch for five shots. Rifles always have the possibility of shooting the occasional very small group, but you might drive yourself nuts trying to duplicate it. Chance says it won't happen very often.

The group might have nothing, or everything, to do with a hot barrel, but even if you heat the barrel again it may not-probably will not-shoot another group that small. At least not for awhile.

Truthfully, if you have a levergun that will honestly average two inches or less for ALL five shot groups fired, it is more accurate than the average rifle.

I usually judge a levergun on two shot groups, which simulate hunting conditions, as it may occur that you'll miss the first and have a chance for another shot. Fire two shots without letting the barrel cool. If you shoot five two shot groups and the two rounds are always close together (starting from a cold barrel condition) you've got a real keeper of a gun and load.

I can't ever recall shooting three times at a deer. Ninety eight percent of the time one shot is enough, which brings up another good way to test a lever. Shoot one shot. Wait fifteen minutes, and fire another. After one hour you'll have a five shot group. How small is it? THAT's how a hunting gun is used. If it's consistent for single shots spaced over an entire range session, again, you've got a keeper of a gun and load.

I've always though leverguns had plenty of accuracy for the hunting they are suited for. The way we test them by shooting groups shouldn't be the same way we shoot groups with, say, a heavy barrelled .22-250.

That said, three quarters inch is damn good for a lever. Rick, how many shots was this group? I think it was two if I read it correctly, but please clarify that for me. If it will do .75 inch for two shots every time the rifle is damn accurate. Please post details of the load, and please do comment on the velocity variation of the carbine-more info for the .35 is always good, I always say.
 

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lantrad,
What Swany and 35 rem said is good info.
If I were you, I'd strip the forestock off the rifle and remove the screw at the mag tube cap to check that the mag tube is somewhat loose on the stud without the screw. This will confirm that the mag tube is not applying force to the barrel. When you can comfirm this, Now do a session at the range shooting the same loads in the same time frames with out the forestock on the gun. If you find your shooting consistant groups without the forestock, you need to carefully check the fit of the forestock to the receiver, mag tube and barrel tenon on the gun. You should be able to re assemble it with out forcing anything
I'd say you'll find the source of your problem in the forestock fit, or the mag tube fit.
If the mag tube is tight on the stud without the cap screwin place, remove a bit of material from the the receiver end of the mag tube until the tightness is no longer present. be careful with the screw out , the cap is under pressure from the mag spring.
Reassemble the rifle and shoot it again, same loads same times, I think you'll be happy with the resuslts.

Tomray
NRA LIFE
 

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Discussion Starter · #9 ·
Tomray, I've completely stripped this gun and cleaned it when I got it. The forearm is solid with no looseness or over tightness that I can ascertain. The mag tube was tested with the wood off to see how snug it was also. Today it shot very well. Last night I removed the washer that I had installed, to guaranty the primer went off, from the hammer spring and rechecked all screws. I did this to improve trigger pull. I shot several rounds before checking the fps just cause I wanted to shoot and to check primer impact. 35rem, I only shot 2 shots cold just to check fps and accuracy. I really worked on breath control and squeezing the trigger for those two shots. They were where I wanted them[1 1/2" high at 100yds] and only 3/4" apart. I'll start another post on the other gun and the velocity spread. Thanks, Rick
 
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