Rifle accuracy issue - I am dumbfounded

[338winmag]

Friend gave me their Remington 700 270 Winchester to reload for this hunting season.
They told me it fired 5" groups and so I figured this would be easy to correct with a good reload.

This rifle shot groups like a shotgun. It took me about 35 rounds to find the "supposed sweet spot", or so I thought. I cleaned it up and loaded the friend 40 rounds to practice with but before giving it to him I thought I would foul the barrel for him and shoot a three shot group in a target for validation.

:shock: The group was back again shooting groups like a shotgun. I went through the whole process of trying to find the new sweet spot. Again after about 20 rounds found the new "supposed sweet spot". The rifle shot 2 3 shot groups und 3/4". I was done, or so I thought. Again I thought I would foul the barrel for him and shoot a three shot group in a target for validation.

:shock: :shock: :evil: Back to shooting like a shotgun, AGAIN! :x

So yes like a fool I went thru this process one more time and this time deliberately shot a three shot group before handing it over to the friend. Oh nooooo. Back to the same shotgun group issue. I don't get it???

In short, unless it is too late to say that... Is it possible this inexpensive Bausch and Lomb scope is the issue. The groups are consistently 2-3" with the reloaded ammo. Often the same pattern. I am going to change out the scope in the next few days but if it is the scope, how does a scope loose zero like this?

Thanks
338winmag

 

[remingtonman_25_06]

270 should be shooting better then that.

Im sure you were smart enough to check all screws, etc.

Baush and Lombs are pretty good scopes. It could be a scope problem, easy way to find out is just to swap scopes for a range session and see what the groups do.

Is the rifle bedded at all? This can help a bunch with consistency, especially if its just sitting in the crappy factory synthetic stock.

What bullets/powders have you tried thus far?

Interesting to see where this goes because I have a buddy also with a winchester model 70 270 that I helped load up some 150g nbts/H4831 and the first outing was great, all loads tried going under 1". Since that first time out, everythings been in the 2" range and I cant seem to figure it out either.

Is it an older or new remington? What model?

 

[cloverleaf]

Well, I took a bushnell of my rifle one time and bought a leupold to fix my groups only to discover eventually it was my reloads. That said, this sounds like a rifle issue, at least thats where I would start.
Are the action screws tight? (too tight?) Is the barrel floated? Bedding look OK? Are the bases and rings tight? To answer some of thesse questions you are going to have to take some things apart. If the bedding, floating looks OK, I would opn the rings and check the base screws etc. How does the crown look? While you got the scope out, borrow another and see how it shoots.
Rumor has it the old Bausch and Laumb had good glass. I dont know how they were mechanically.
As I said, in the end my issue was my reloads. 2 extra grains of powder opened my groups up 4c inches. In my experience cheap Bushnell scopes have a tendency to loose there zero but Ive also proven that the "nut behind the trigger" can be the problen too. Your in the right place for good advice (not necessarily mine). Just like reloading, change one thing at a time. I haventreally asked new questions or given you any new insights I guess. I hate the variable too. Good luck! Stay with it and let us know what you find. We will learn from your misery. Hope ours can help. CL

 

[gerry]

I'm sure you will get all sorts of suggestions but one thing overlooked is do you have a tool to test bullet runout? When I got my 264 WM I bought about 300 new WW brass only to find out they were awful when I measured my reloads for runout can't tell you how bad the stuff was. Without my RCBS Casemaster I would have been pulling my hair out trying to get the gun to shoot well. From the research I was able to do (on 24hourcampfire and Handloader magazine) for hunting loads .003 or less was a good cutoff. It really helps to sort loads the gun groups really well with good ammo but with the crappy stuff it's all over the map. When I had my Savage 30-06 I did a bullet experiment with loads .003 or less it would group under 1 inch with the .003 plus loads it was over 2 " groups. The 264 WM brass was far worse in quality to the 30-06 brass can't tell you how bad some of them are Nosler 264 WM brass has been very good by the way. This may have nothing to do with your problem but I wonder how many good guns and loads have been scrapped because of bad brass (or dies that resize brass crooked).

 

[338winmag]

Thanks all! Some good thoughts.

I have tested action screws, rifle screws scope screws. All are secure and tight and not over-tight. To be honest, I don't know a bad bed from a good bed (except the one I sleep in), so I cannot state one way or another on this. Regarding the crown; this might be a possibility but it has a muzzle brake on it and I do not want to remove it without owner's consent to check the crown. I have a few cheap scopes that I believecan atleast test and rule out the possibility that it is a scope. Ranges are closed today so I have to foot tap till at least tomorrow or Wednesday before I can test. Also I am going to ask the owner if I casn indeed remove the current scope first. (Its always a good practice to ask)

I do have equipment to test runout and these nullets are between .0005 and .0018 so I have ruled that out. My logic behind not necessarily considering this is the rilfe was and still does shoot 3.5"-5" groups at 100 yds with over the counter ammo (two brands that use dfferent brass). The brass is Winchester brass. As virgin brass custom reloaded, it shot the same bad groups; as fire-formed custom reloaded, it shot the same bad groups. The exception is 3 times I had two 3 shot groups firing less than 3/4" or less half inch groups. I figured I was then done only to come back to the range and the groups were way off zero and shooting like a shotgun.

All the rifle says on it is Remington 700? Nothing else. Nice looking checkered wood stock and thick recoil pad. The sweetest trigger I have ever squeezed aside from a custom 300 win mag that I have reloaded for.

After looking up on Google, I see that it is one of the older 700s. I will test with another scope probably on Wednesday and advise with the results.

 

[elkeater2]

I hope you find a solution, these puzzles are part of what keeps some of us enthused, as twisted as that may sound. I'm a 'fixer' or think I am. I want to be, but the family has learned to say no to some of the things I try to fix. :grin:

I wonder about stock bedding.
I wonder about scope mounting, also. I have to admit getting mount screws mixed up, and using some that were a hair too long - the screws were tight in the holes, but the base could still wiggle around!

B & L scopes are subject to problems, as they all are. For years, they peddled them with no adjustments, as all the adjustments were in the mount. They were not as experienced making decent internal adjustments as their competitors for awhile.

I wonder about throat and chamber alignment, and finish in that area. If the chamber and throat are not centered, then rifling engagement of the bullet occurs on one side before the other. Line that up with runout (total cartridge runout, bullet runout, chamber runout, ?? ) - line it up the right way and things go good. Line it up the wrong way and it's like trying to drill a hole with a bent bit.

I got the stuff and started making chamber casts, just to satisfy my curiousity.

So, mostly food for thought. Let us know what you find out!

EE2

 

[338winmag]

If it is bedding, I won't know.

"I wonder about scope mounting, also. I have to admit getting mount screws mixed up, and using some that were a hair too long - the screws were tight in the holes, but the base could still wiggle around!" <-- I did take apart and tested all mounting screws for base and rings. Everything checked out.

I have since mounted a new scope on the rifle and have to wait till Wednesday to see if it is the scope. I sure hope it is That is an easy fix.

Thanks All
338WinMag

 

[filmjunkie4ever]

Sounds to me like a bedding issue...my father bought a brand new Rem 700 Custom Deluxe about 15 years ago and it was shooting erradic groups as well. One day he took a dollar bill and slid it down the barrel channel and found out that there were high spots in the stock that were touching the barrel and not allowing it to "free float." So after a little work with a dremel tool and sand paper, and resealing the whole barrel channel with Lin Seed oil we had a shooter. Has shot amazingly since then. Here's how you check that.

Another Remington I was asked to work on for a friend needed some help as it too was shooting patterns instead of groups. I ended up taking half of a business card and placing it under the barrel at the very end of the barrel channel of the stock to give it a bridge as its called. His rifle has shot well ever since.

So those are two easy things to check on the existing bedding. I think this is what Remmy 25-06 was trying to tell you. There is also the possibility that you may need to glass bed it.

 

[DrMike]

So, do you always keep British currency to check your barrel channels? :lol: Good looking picture, but somewhat more expensive than a dollar. :shock:

 

[filmjunkie4ever]

Haha good point...no I grabbed this off of google because I was too lazy to take a pic of my own American dollar in my own American Barrel Channel and then upload it to my picture host website and then repost it here. Haha, guess I should've looked for an American bill.

Way to keep me in check Dr. Mike, I might've been listening to "God save the King" and drinking tea by this afternoon had you not stepped in... :grin:

 

[DrMike]

I might've been listening to "God save the King" and drinking tea by this afternoon had you not stepped in...

Next thing you know, you'll be sharing high tea with cucumber sandwiches and biscuits with your tea (Earl Grey, of course). Consequently, it is "God Save the Queen," at the moment.

 

[NoelW]

Saw a 7mm Mag. shoot like that one time. It had a tight spot in the barrel and after just a few rounds would be copper fouled so bad you could hardly get a cleaning jag through that spot. The copper fouling could be removed and it would shoot ok for 10 rounds or so and start the same thing again. BTW that was an old 700 Remington as well.

 

[filmjunkie4ever]

I have typically had worse luck with the Remingtons made in the last 20 years or so than the old ones.

I have a 25-06 made in the 70's, a friend has a first year production 700 in 7mm Rem Mag with the Eurpoean style checkered BDl stock, and they both shoot just as straight and problem free as my Model 70's do. Never had any trouble with either....same with the 721's I have dealt with.

But like any gun, you are going to find one of every make here and there that may just be a lemon or just need a bit more attention to shine.

 

[JD338]

I am also thinking it is a bedding issue. Is the barrel floated? You could also use a piece of an old credit card cut to fit the action and put in front of the recoil lug. this will float the barrel.

It could also be loose mounts or even the scope. In order to check the mounts, ypu will have to pull the scope. It might be worth trying a diffeent scope.

JD338

 

[Guy Miner]

All the usual culprits have been identified:

bedding

free-float barrel (interestingly the rare barrel seems to need a pressure point)

scope mounts not tight

problem with the scope itself

Bedding the action and free-floating the barrel will likely cure the accuracy problems - unless the barrel needs attention.

If the crown has been dinged - it could lead to poor accuracy. That's a quick and inexpensive fix.

Also, it may be shot out. The .270 isn't a "barrel burner" like some high intensity cartridges, but not far from it. A quick check of the throat area with a bore scope can determine the condition of the barrel. They do wear out. If someone was an enthusiastic shooter, they could easily have put enough rounds through it to toast the barrel. I'm getting close on my .25-06 Rem 700 and it's only a few years old.

Then you've got several choices - one of which is to simply have Remington re-barrel it. In the old days, that was a very good idea. Their production barrels were pretty good. I'm not so sure anymore.

Or go with a full custom barrel from Krieger, Pac-Nor, Hart, Lilja or ??? Only problem is, that this can easily result in more expense than the rifle is worth.

I'd exhaust all possibilities before re-barreling. Try a different scope. Tighten down all the mounts and everything else. Bed it. Free-float the barrel. Who knows? Somewhere along the line you'll find the accuracy you seek. A custom barrel on an old rifle isn't a bad thing. Not at all. It's just expensive. Then again, the doggone new barrel will likely last several thousand rounds.

Regards, Guy

 

[eric 270 wsm]

just wondering if I under stand it right that you are cleaning the rifle after finding the sweet spot and then firing retesting and grouping is all over the place. that may be your problem.

 

[Guy Miner]

Good thought. Clean bore vs seasoned bore.

 

[Antelope_Sniper]

As guy said, it could be shot out.
The first few groups after cleaning shooting shotgun patterns, followed by a few good groups before they enlarge again is a classic sign of a shot out throat.

I would try all the classic solutions already mentioned first, starting with free floating the barrel. If none of them work, I'd have a good smith "set it back a thread or two", and clean up the chamber. This can normally be done for about $125.00.

 

[usmc 89]

you may want to check and make sure the lead base screw is not pushing on the barrel threads if you havent.

 

[ROVERT]

So, do you always keep British currency to check your barrel channels? :lol: Good looking picture, but somewhat more expensive than a dollar. :shock:

I thought the same thing when I saw that. I currently have five quid in my wallet, but I'm guessing the average reader of this forum doesn't. Just don't try to check a barrel channel with a pound rather than a dollar. It would be extremely free floated I suppose.