# 300RCM trouble



## big_mike_338WM (Oct 27, 2010)

so i bought a 300RCM a while back...and im learning its a pain in the butt to sight it in. i usually do 3 shot groups for sighting in. well this rifle dupilcates (and in some cases out performs) the 300WM (but does so with a 20in barrel and a short action) well the barrel heats up fast and 2nd shot grows a little and the 3rd shot is almost always about 3-4inches out of whack ( i know some of you think a 3-4inch group at 100 is fine but i like my groups as tight as possible). now when its sighted in and with a cold bore shot it is a tack driver but my last Mt. goat hunt i bumped the scope pretty good and need to get it back up to par...any one have an easier or faster way to help me get thins goofy thing sighted in faster with out taking a shot and letting it cool down for a few mins?? luckily i still got my 338 so its not a huge rush to get it sighted in but i live in AK and winter is coming fast and i would like to have it done for spring bear season...thanks for any help guys


----------



## ac700wildcat (Oct 30, 2006)

If it is off by that much after the barrel warms up you must have an issue with bedding or the barrel isn't freefloated. You might need to get it to a gunsmith to get it checked out if you don't want to have to continue to deal with the problem. You could also just waste five mins between shots and let the barrel cool down. It might be a bit boring, but its probably the easiest way to deal with the problem.


----------



## KurtR (May 3, 2008)

If i had a gun that groups opened up like that after only 3 shots it would either be down the road or to the smith. I shoot nothing but 5 shot groups at the least and most of the time 10 shot groups to get a true picture of what the gun is capable of. You need a new stock or new bedding and if you had good rings and bases just think you would not have this problem as it would still have its zero.


----------



## Plainsman (Jul 30, 2003)

With shots moving four inches at 100 yards there is some serious problem. There could likely be abnormalities in the metal of the barrel. A few years ago the people performing cryogenic treatments made a lot of money solving the issue your speaking of.

The most likely culprit is contact with barrel and stock on one side. Light barrel rifles with heavy loads often don't do well when free floated, but rather perform best with measured forend pressure. With this type of rifle I most often free float it, then bed the action and forward one inch in front of the recoil lug. I then take it to the range with a handfull of business cards. Slide one, two, or three business cards (whatever it takes) between the forend and barrel until it's just snug. Shoot three shots, let it cool, and add another business card. I have no way to measure forend pressure, but I had a light Winchester 300 Mag that grouped three inches from the factory. It grouped four inches free floated, and grouped 3/4 inch after adding forend pressure. When the groups start opening up again it's time to remove one business card.

Take your rifle home, Cut the front 1/2 of the business cards off, put them back in place leaving about one to two inches of forend gap. Fill that with epoxy bedding and your problem should be solved.

Some falls and bumps are bad, and I would not jump to the conclusion that your rings and mounts were not adequate.


----------



## KurtR (May 3, 2008)

put some badger or seekins on there and you dont have to worry about any bangs or bumps unless the scope is cheap to.


----------



## southdakbearfan (Oct 11, 2004)

Definately sounds like a bedding issue. The tubes on the RCM's are fairly beefy if my memory serves me correct, and they are also using some fairly fast burning powder in them.

I would free float the barrel and see what happens, if that doesn't work, which I believe it will, then you could go with bedding the action/recoil lug or the whole works. I have seen many rifles go from 3-4 in guns to sub 1 in with very little work.


----------



## big_mike_338WM (Oct 27, 2010)

thanks guys!! i think im gonna talk to my uncle about bedding the acton and floating the barrel. im not worried about the rings and bases being bad ...my uncle and i both have many ruger rifles and they seem to be a pretty decent set up...and i didnt just "bump my scope,i fell off of a cliff that was about 5ft and landed on my gun thats why its not shooting straight. and the barrels on the RCM's arnt real beefy they are a sporterized barrel. but yea i will deffinatly try to see what i can do about getting it fixed. i did try to drop down to the 165grn bullets (i usually shoot 180's) to see if i could reduce bearing surface by shortening the bullets...but it didnt work, i think since it pushes them harder it makes the barrel just as hot. and i think i forgot to mention that after several shots( about 6 or so) the barrel is almost too hot to touch...im almost worried that i got a lemon...but we'll see i'll try floating the barrel and bedding the action and see what happenes!! thanks again guys!! keep the comments and ideas coming!!


----------



## Savage260 (Oct 21, 2007)

"and i didnt just "bump my scope,i fell off of a cliff that was about 5ft and landed on my gun thats why its not shooting straight."

Maybe there is more wrong than just bedding then? That seems like a pretty violent jolt, no telling what might have been damaged.


----------



## big_mike_338WM (Oct 27, 2010)

yea i think im gonna take it out of the stock and reset it to see if that helps...and it has always had this problem with the groups spreading out as i shoot it


----------



## ac700wildcat (Oct 30, 2006)

If you are shooting your rifle until the barrel is too hot to touch, you are probably doing damage to the barrel. Personally I let my barrel cool down to luke warm between shots and at most I'll shoot three time before letting the barrel cool way down. Try waiting five or so mins between shots and see what happens...........


----------



## KurtR (May 3, 2008)

People ruin more barrels from excesive cleaning than they do over heating. If you clean before accuracy drops off you are doing it to much


----------



## Plainsman (Jul 30, 2003)

KurtR said:


> People ruin more barrels from excesive cleaning than they do over heating. If you clean before accuracy drops off you are doing it to much


That is a very inclusive statement. I would say it depends very much on your cleaning methods. Often new cleaning methods are much less destructive than pushing a bullet down a dirty barrel. As a matter of fact I would say that careful non abrasive cleaning is much less destructive and causes less wear. Clean from the breach, and clean often with little or no abrasive techniques. Perhaps the key here is your reference to "excessive", but if your careful I don't think you can clean excessively. Some bench rest guys clean with every shot.


----------



## KurtR (May 3, 2008)

Frank(LowLight) the owner of snipers hide is doing a little test on cleaning and last i saw he was at 1800 or so rounds between cleaning with his 260 rem and still shoots 1000 yard 18 by 8 target at 1000 with ease. If it is wet or enviromental conditions call for it of course you have to get rid of moisture. But till accuracy drops off there is no reason to clean it. I guess if you want to get a more technical and better explination go on there and ask or check it out.


----------



## southdakbearfan (Oct 11, 2004)

Cleaning is very dependant on the rifle, some factory rifles foul very fast, some custom jobs or rifles with hand lapped barrels can go very long times.

I personally have had the experience of dealing with a winchester model 70 classic sporter in 270 weatherby that fouled in less than 6 rounds, destroying accuracy due to excessive copper fouling.

Back to the topic, falling 5 feet? Did the gun shoot straight before? If it did, did you put a slight kink in the barrel? Damage the crown? If it did shoot good before, you may want to check into those before you do a bunch of bedding work.


----------



## big_mike_338WM (Oct 27, 2010)

southdakbearfan said:


> Cleaning is very dependant on the rifle, some factory rifles foul very fast, some custom jobs or rifles with hand lapped barrels can go very long times.
> 
> I personally have had the experience of dealing with a winchester model 70 classic sporter in 270 weatherby that fouled in less than 6 rounds, destroying accuracy due to excessive copper fouling.
> 
> Back to the topic, falling 5 feet? Did the gun shoot straight before? If it did, did you put a slight kink in the barrel? Damage the crown? If it did shoot good before, you may want to check into those before you do a bunch of bedding work.


yes it did shoot well before i fell...and i took it to the range the other day and put a few rounds through it (i didnt sight it in) and it still shoots great on a cold bore shot...right now its about 3'' right and about 3.5''low at 50 ...but the same thing as i shoot the groups grow...but cold bore shots seem to be the only way to sight it in...im at a loss ...any one else have the same rifle? my uncle got the 338RCM and he can keep them in a pop can at 200...is my gun just not a "shooter"?


----------



## Plainsman (Jul 30, 2003)

> I personally have had the experience of dealing with a winchester model 70 classic sporter in 270 weatherby that fouled in less than 6 rounds, destroying accuracy due to excessive copper fouling.


Yes, and I have run into that more often with Rugers. Great rifles, but I think their bore is slightly more rough than others.

Big Mike are you sure this happened suddenly, or is there a chance it was more gradual than you think. Southdakbearfan's post struck a cord. Have you been using copper solvents? Perhaps you have already answered that I didn't go back through all of the posts. It will be different from rifle to rifle. I have only experienced about 40 or 50 rifles (personal rifles) and accuracy has always fallen off. It occurred with only 20 rounds out of an old Ruger, and the top I have experienced is about 200 rounds with a highly polished bore.


----------



## KurtR (May 3, 2008)

I must have got lucky the rem 700 has 415 rounds from last serious cleaning. i have ran bore snake through it a few times. It still shoots as good as it did from the first day i shot 100 rounds through it with no barrel break in which is a myth made by barrel makers. tommorw will be another 100 168 amax to add to round counts between cleaning


----------



## big_mike_338WM (Oct 27, 2010)

Plainsman said:


> > I personally have had the experience of dealing with a winchester model 70 classic sporter in 270 weatherby that fouled in less than 6 rounds, destroying accuracy due to excessive copper fouling.
> 
> 
> Yes, and I have run into that more often with Rugers. Great rifles, but I think their bore is slightly more rough than others.
> ...


no it wasnt a grudual thing...it has done this since day one straight outta the box...i always just thought it was the barrel heating up. but i dont know now...i want to try taking it outta the stock and re-setting it...i mean i know the barrel heating up will make the groups grow but i didnt think it would do so that fast...and and the way i celan it is just with a bore snake...and the barrels isnt fouled up or anything


----------



## southdakbearfan (Oct 11, 2004)

So it has always strung it's shots out as it warms up? Or it started doing it after you fell?

If it has always strung it's shots, does it have a pattern to them, like the hotter it gets the farther one way the shot goes? If so, I would then lean towards a bedding issue.

If it didn't do this until after you fell, then I would lean towards damage/jarring something.

Also, have you tried different bullets/weights?


----------



## big_mike_338WM (Oct 27, 2010)

southdakbearfan said:


> So it has always strung it's shots out as it warms up? Or it started doing it after you fell?
> 
> If it has always strung it's shots, does it have a pattern to them, like the hotter it gets the farther one way the shot goes? If so, I would then lean towards a bedding issue.
> 
> ...


ok so it has always done this ...the only reason me falling is relevant is because i knocked it outta zero and i need to re-sight it in...and yes there is a pattern...kinda... they usually start shooting high and right (the first 2 are usually pretty close) then the 3rd is usually about 3inches or so high and about 2 inches right (those are just esimates i havnt actually measured it or anything) and yes i have tried different bullet weights i havnt had my unlce reload for me yet so im stuck with facorty ammo for now...what i usually try to shoot is the 180's (2900fps w/20" barrel) and they spread out so i tried dropping down to the 165's (i think those are about 3050fps w/ same 20" barrel) and i thought that by dropping to the 165's that it wouldnt heat the barrel up so much (by reducing bearing surface on the barrel) but i think since they push them harder it heats up the barrel... but they do about the same thing. Now i did have some 150 grainers that i bought just to shoot at coyotes and stumps or what ever just so i could have some brass...i never tried printing them on paper though


----------



## southdakbearfan (Oct 11, 2004)

Ok, I would definately lean towards a bedding issue.

The more the barrel heats, the more it expands and wherever it is contacting the wood/stock in the barrel channel, it is pushing against it, causing the shot stringing. The hotter it gets, the further it goes out of whack I would suppose.

I would first start with just free floating the barrel by sanding out the barrel channel until a dollar bill slides freely all the way back to the action. I actually go with a folded over dollar bill, but everything I have read says a dollar bill should be sufficient. Once there, take it out and try it.

If that doesn't work, well then you can get into the glass bedding with the action/recoil lug, or the whole works if you so wish.


----------



## big_mike_338WM (Oct 27, 2010)

yea i think im gonna try it...i dont know what else to do...has anyone else have the same gun with the same problem...or know of anyone that its ahppened to?? or did i just get a rifle that needs some work?


----------



## southdakbearfan (Oct 11, 2004)

All my rugers shoot well, but all needed free floating to do so.

I glass bedded one, but that was basically a shot out ruger I bought and rechambered with a new barrel, the rest all walked the shots up one way or another as the barrel heated up. Free floating took care of the issue. I also ended up doing some trigger work, but these were the old triggers that were really heavy. I believe the new ones are much better with the LC6 trigger.


----------



## big_mike_338WM (Oct 27, 2010)

ok thanks!!!!! i think im gonna try floating the barrel...so far it seems like its the best idea, if that dosnt work then i guess i'll try bedding the action...i hope it works!! thanks for all the help guys!!!1


----------

