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Discussion Starter · #1 ·
Just got in from shooting a 336 RC, 35 Remington, that I bought used. Shooting 150 grainers at 50 yds. holes in the target were almost perfect. Using Winchester and Remington 200 grainers....both tumbled and keyholed at 50 yds and 100 yds. Slashes were about an inch and a half long. I returned the rifle to the place that I bought it and they had me leave it for the gunsmith, along with the four targets and two samples of the 200 grain bullets used. The bore is clean and the micro grooves still have a great deal of depth. The crown is good. It looks like the action might be feeding the 200 grain bullets in too far so that they touch the lands. The 150s are more pointed; the 200s are round nosed. The two sales fellows, both knowledgeable, want the gunsmith to look at it, using fingernail polish to see how far it feeds into the bore and if it is touching the lands, and said, there is an adjustment on the Marlin 336's that can correct the amount of feeding that takes place. Anyone with any experience on that end know of this happening before, or having adjusted the action in their own gun to correct such a problem? or what causes a bullet to tumble?? Thanks.
 

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First thought was crown, second undersized, third is rate of twist not sufficient to stabelize the length of the bullet.
 

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Or Rifleing all plugged up with lead , smooth bore instead of grooved
 
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Discussion Starter · #4 ·
hmmm....given my situation: why would the 150 grain bullet spin properly (clean holes, thus gripping the micro-grooves)and the 200 grain bullets not spin and tumble instead?
 
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Discussion Starter · #5 ·
Sure-Shot has the answer, seems like it's gotta be a, b, or c.

.35's usually love those 200gr bullets.

You said you bought it used, maybe somebody trashed the bore with an ambitious hand-load and then sold it off. See any odd "rings" while inspecting that bore?

:?
 

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Sure-Shot said:
First thought was crown, second undersized, third is rate of twist not sufficient to stabelize the length of the bullet.
99 times out of a hundred, tumbling occurs when bullets aren't spun fast enough. The heavier the bullet, the faster spin it needs.

Shum8
 
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Discussion Starter · #7 ·
There were no unusual "rings" in the bore ....the bore looked very bright and shiney and the grooves appeared to be deep, .e.g., there were no visible places where the grooves disappeared or where the bore was solid shiney/bright...the bore light did not indicate any problems there...I didn't use a bore foam on the micro-grooves and the folks at the gunshop didn't see any indication that they were dirty or clogged in anyway. THe crown was not chipped in any way or worn unevenly. As I mentioned....they thought the 200 grain bullets were longer than the 150s and loaded into the chamber with the tips pushed up against the lands.

My own look on the internet turned up these:
There are three reasons why a bullet tumbles after leaving the barrel:

* The bullet's base is cockeyed and gas escapes off one side before the
other as it leaves the muzzle.

* Something really unbalanced the bullet as it was going down the bore.
After exiting the muzzle, it tumbles.

* The bullet is spinning way too slow as it leaves the muzzle; it won't
gyroscopically stablize. Or it's spinning too fast; its natural
unbalance creates enough centrifugal force to cause it to tumble.

and this:

A properly stabilized bullet (that is, one spun with sufficient rotational speed by the rifling) does not tumble in flight, but may tumble upon impact with a soft target. If a bullet were to actually tumble in flight, its accuracy would be so bad as to be unusable. What does happen is, that due to aerodynamic lift on the bullet and minute inconsistencies in the location of the bullet's center of gravity, that the bullet's point may precess slightly, that is move about the centerline of the bullet's flight, but the bullet remains point forward. This precession is quite small and if the rotational speed of the bullet is optimum the point precession dampens out to a negligible amount in a process known as "going to sleep."

1) I think either the micro grooves are partially clogged/dirty ...there is more lead from the round nose bullet dragging than from the 150 grain, more pointed bullet;
or 2)the bullet may actually be touching the lands (between the grooves) before being fired, and is "unbalanced" as it proceeds down the barrel. (a head space problem?)

I won't know what is going on for sure, until I hear from the gunsmith...but...I'll post his "verdict" when I hear from him. It is a puzzlement! :lol:
 

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I think Sure-Shot probably nailed the problem with the first two ideas.

Even a 200 grain bullet is short enough not to need a lot of spin - unless it is also not moving fast enough in velocity. If a bullet is close to its minimal rotations/distance ratio, it can sometimes stabilize properly or not depending on its velocity. IOW, it needs certain rpms (rps) to have gyroscopic stability. For example, a 22-250 may be able to stabilize a certain long/heavy bullet with a 1-14" twist while the same bullet in a 222 with the same twist rate barrel may not stabilize. Both bullets spin at the same rate but the lower velocity bullet is also spinning slower which prevents it from being stable. That may be the problem with that 200 grainer. Is your barrel short and/or do you know what velocity you're getting with those 200s?
 

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Measure the bullets and see if there is any difference in the bullet diameters. Undersized bullets aren't unheard of. Microgroove rifling, only from what I've read, may require slightly larger bullets to shoot well. Don't let anyone change your rifle until you check the bullets.
 
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Discussion Starter · #10 ·
direwolf - I will measure the bullets dia. and the OAL of the cartridge this evening.

Golsovia - the barrel is 20 inches, (the mag tube also extends to the end of the barrel) I believe (I don't have the gun here right now.) and the rifling is 16rh twist, micro-grooving. I will go to the gunsmith's and check it tomorrow. As I said before, the Crown is not damaged, or chipped. As to the spin on the bullet....why would it shoot well with the 150 gr. and so horribly with the 200 (two different factory loads...both keyholed at 50 and 100 yds) if the rifling was deep, no shiny areas or indication of wearing and the barrel and twist are the standard sizes that others shoot well with? Perhaps the bullets are undersized...I will check that shortly, but even that seems highly unlikely (to me) for two different factory loads from two different manufacturers. Of course, starnger things have happened....but...
The gunsmith will not make any changes without talking with me...he is to see if he can diagnose the problem for the present. It should be under the store warranty as it is less than a week old since the purchase.

I am not trying to be argumentative with possible ID of the problem (and I hope that is not anybody's perception of my responses)...just trying to understand why/how it could be. I do appreciate the input
 
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Discussion Starter · #11 ·
I took 5 bullets out of each box at random:
200 gr Remington Corelokts
bullet dia OAL of cartridges
.355in 2.518 in
.353in 2.522 in
.355in 2.512in
.353in 2.515in
.354in 2.511in

Winchester X 200 gr. Power Points
dia OAL
.352in 2.511in
.351in 2.517in
.353in 2.511in
.353in 2.517in
.352in 2.516in

the bullet measurements are above the cannelure and crimp on a loaded factory round...358 is called for on the bullet dia. It may be that the rear of the loaded bullet meets the .358 dia. I have no way of telling that since it is already factory loaded. maximum allowable COL is 2.525"
 
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Discussion Starter · #12 ·
update- Tuesday, Nov.22nd:

The gunsmith locally has no idea what the problem is....suggested to shoot only 150 grainers....I said...no. no. no...forget that idea. I bought it to reload for it and shoot the full range of what's available....either fix it or give me my money back. So, they are sending it to the Gander Mountain Headquarters and a gunsmith there. I have a sneaking suspicion the bore has been changed. It sure doesn't look worn out. Anyways, it will be a week to ten days before they get it back. The mystery saga continues.... :lol:
 

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tumbling bullets report question for Ruger Cal 480

Maybe I missed it , but sure would like to know the out come on your Nov post. Last I understand , the rifle went back to Gander Mt gun smith........................ Thanks ,,,,,,,,,,,,,MUTT
 
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Discussion Starter · #14 ·
I will be back home in Pennsylvania at the end of the month, and hope to get out to the range as soon as the weather permits. I have cleaned the gun and will recrown it. Also picked up some of the new 35 Remington ammo while in Florida. I plan to recheck the forearm bands . The gun is clean....grooves are cleaned of copper and lead. If it still tumbles, then I will be contac ting Marlin. The Gander Mountain gunsmiths claim the crown is good and there is no evidence that the barrel has any problems. Will keep you all advised of the progress or lack of it in finding answers.
 

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Regarding your measurements of the bullets in the factory ammo, it was common knowledge years ago that Remington is fond of using two-diameter bullets in its ammo, something that used to drive ballisticians NUTS. The front section is made smaller to reduce bore friction, riding on the lands, and the base is full-caliber to help with obturation (sealing the bore). Given that they've sold millions of rounds like that with few complaints, I doubt they've changed anything.

And while most guns in 35 show a distinct preference for either the 150 or 200 grain bullets, keyholing is just flat weird. Keep us posted on this, I've been waiting for an answer since November, and I'm still interested!

Papajohn
 

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Ruger480cal

Check your Private Mail !

Tomray
NRA LIFE
 

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Ruger cal480,
Were I a betting man, I would bet the bore of your 35 has been firelapped or handlapped to the point that the rifling no longer has sharp corners to firmly grip the bullet. The 200 grainers require more spin and being heavier are harder for the rifling to get them to spining in the first place. Your description of the bore being really bright and shiny seems to bear this out. On the Beartooth bullets web site the technique for firelapping is described and recommended to remedy tight spots in the bore, which they say also improves accuracy. They also sell the kit to do this with. I think temptation got the best of your guns previous owner and he really overdone it. If you have a way to fire a 200 gr. round and recover the bullet still in good shape it may show signs of the bullet stripping in the rifling. My two cents, sir.
 

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RugerCal480,
Forgot to answer your question. The bolt in the rifle action locks up exactly the same every time. There is no adjustment to the action. The barrel along with the chamber it contains will only change headspace. If the chamber is short as the two "salespersons" are saying, the gun wouldn't chamber a round fully enough to fire. Remedy would be to rechamber the gun to SAAMI specs.
 

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Okay! Are ya ready for an answer?? Gunjunkie apparently hit the nail on the head. I had my local gunsmith check the rifle over and clean it for a fourth time! The gun now shoots all 35 remington ammo without keyholing at both 50 and 100 yds. Apparently the rifling was really fouled. The smith said he cleaned it and soaked it, and cleaned the mechanism as well. That was it. I also had him install the trigger from my 1895CB that was replaced with a Wild West World trigger. I had it out shooting today and it shot Leverevolution 200 gr, Remington 150 gr. and Remington 200 gr Cor-lokts...all with no trouble ....all targets showed clean round holes with no key holing whatsoever. Much thanks to all who contributed ideas to check, this one turned out to be simple....the gun was dirty! Best cheap gun ($125)I ever bought!! :lol:

Now to reload for it, after I get some more rounds for the 45-70 and 45LC reloaded!!
 
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