Home Forums Reloading Varmint Rifles Accuracy issues with my new 243?

Is the magazine box touching the bottom or sides of the stock? Barrel floated or touching the sides of the stock? Have you tried a different scope or scope ring? If its not bedded have you played with the action screw torque?

Barrel is floated, Mag box unsure but will check. Stock was bedded , but for a different 700.

HeavyBarrel

I would re-bed for sure.

There's all sorts of possible issues if the stock isn't bedded for THAT action, so I'd think hard about at least trying a "skim" bed, making sure the old bedding is ready for adhesion of any new bedding.
The first and easiest way to get a clue is to either cut up some credit card or business card shims to temporarily float both the action and barrel. Just make sure the recoil lug is in contact with the shoulder as you tighten it down. But I've done that numerous times to get a clue and it can be amazing, almost night and day.
The other think you'd want to do is check your contact with either inletting black (ick) or Prussian blue (also ick). But either will force you to "clean up" and prep the old bedding for the new skim or re-bed.
I had to do that a couple of times, what I did was apply the blacking, crank stuff down as per usual, and then shoot the rifle. Then I pulled the action and that revealed the extent of contact without any doubt.
And the mag box might be secretly ruining everything. I don't know enough about Rem B and CDL's to know how the mag box is made, but if it's separate from the bottom metal, you could probably pull it out and shoot naked single shot and see what happens. Also, the shim trick above should get the bottom metal away from any action contact/stress, too.

Worked through some issues very similar to yours with a buddys model 7 7-08. The barrel would foul and start tearing jackets up accuracy would go to pot. A hard cleaning would bring things back but only last for 10 rounds or so then start opening up again. It was a shame he really liked the gun but lost all faith in it. He ended up trading instead of putting a new tube on.

Have a Ruger m77 mkii, 300 win mag. Hand lapped barrel before shooting. Went through a strict barrell breakin. Best i could get is 1 1/2" out of handloads and the best factory ammo. Just for chits and giggles i grabbed a box of Rem 180gr xpress. The Cheapest ammo you can buy. 4 3shot groups that clover leafed. This box had been on the shelf for a couple years so next time I was at wally world grabbed a new box and had the same result. It has dropped several deer out to 650 +/- with out fail. Just sayin some guns like the cheap stuff.

What procedure did you use?

Bore guide. Do not let rod rub barrell crown or chamber. 30 cal jag with 1 patch with Rem bore cleaner. Pour boilng hot water thru bore to remove any machine oil polish until your arm falls off. Next nigbt repeat. When finnished boil water and pour through barrel. This will remove remaining polish. Hold barrel with a rag it will get hot. Break in 1 shot and clean 20 times cheap ammo. Then 3 shots and clean.

I have done this to several factory rifles and tbey all shoot above average for the class.

I used this process on a Kimber VT Long Master. It shoots one hole at 100. My best shot was a PD at 725.

Rifle is at gunsmith now. Being re-bedded and crowned. Got 20 or so different combinations loaded up and ready to try. Will keep yall posted on how it does.

HeavyBarrel

Try some Bergers. If it won't shoot Bergers , it won't shoot.

In 2008 I bought a new Rem 700 BDL in 243 thinking it would shoot great because I had two other 700s that shot within .75 MOA (22-250 and a 338 RUM).

Not so fast. The damn rifle was lucky to shoot groups inside 4 inches!!

Everything I tried - no luck - to include changing scopes.

Finally broke down and bought the first box of factory ammo since 1965 and same result.

I contacted Mother Green, and their response was that the rifle "shot within factor specs" and they would do nothing about it!!!

I rebedded the action and got it to shoot within 3 inches.

Recrowned and got it within 2 1/2 inches.

Figured I had a lemon and had two choices. Rebarrel or trade and buy another 243 and risk another lemon.

So I rebarreled to a 243 Ackley. Never made a better choice in my life. That rifle drives tacks and I never worry about trimming the brass.

Will never buy another Rem 700

Barstooler

Barstooler, what sort of performance improvement did you AI rebarrel get you?

85 sierra bthp. .030 off the lands, lapau brass, I 4064 amd 210m.

Update on .243. Got gun back from smith today. Had it re-bedded and crown touched up. Got home, mounted and torqued scope, and action and tried some ammo I had loaded and ready for trial. Had some 70gr Speer TNT loaded with 47gr of IMR 4350, 5 to be exact. Shot all five after fouling barrel and getting scope close with some factory. Printed a nice 3/4"group! Pretty pumped so I had some 80gr Barnes TTSX's loaded up with 4350 and they did about 2" for a 5 shot group. Had 5 Speers's loaded with varget, same OAL as the first Speers's with 4350 and it did about a 2" group with those five. Had some more Barnes loaded with Varget and they did 2" or slightly a little more. Loaded about 20 more Speers's with the 4350 at same specs as the first that shot 3/4" but ran out of day light so I have yet to confirm. Cleaned the bore really well and will give them a try tomorrow.
Will keep yall posted and hope that it wasnt a fluke!

HeavyBarrel

I "built" a 243 out of a Savage 110 300 Win Mag by changing the magazine, bolt head and barrel which was easy. Got it sighted in in 8 shots with the last three almost touching 1 inch high at 100 yards. 43.0 grains of AA4350 and the 85 grain Nosler Partition. Can't wait to see how the 95 grain Ballistic Tips shoot. I wanted to AI this barrel and still can but ti would only be to stop the incessant trimming but I can just toss the common brass after 4-5 shots and go on with it.

Shot the 243 this evening again. Seems to like the Federal Fusion 95gr factory with 5 in less than 1.5" sometimes less than 1". I decided that after not getting the repeated good groups with the IMR4350 that I would give IMR4064 a try. Glad I did, it shot 5 within an inch 2 different times. Bullet was Speer 70gr TNT at 2.625 OAL and 40gr of 4064. i also loaded 5 at 40.5 and they shot within an inch. Ran out of light but got 5 loaded up at 40.5grs and seated the bullets out a little further. I ran out of light but will give them a try soon and try several different seating depths to see if I can tighten them up a little. Looks like gun may turn out to be a keeper but it seems really finicky, more so than other rifles I have worked with.

HeavyBarrel

and I get flack from some guys on the campfire, when I speak of what a good choice 4064....

just FYI, I shoot the 70 TNT using the old IMR Brown Sheet load data for the 80 grain Sierra.. which is 42.5 grains..

If you can't find 4064 when you run out, IMR 4895 will take the same load data.. at least in each of my 243s, past and present...

3031 is also a darn good choice if you can't find the above two powders on the shelf... .but IMR powders haven't been having an availability problem for quite a while...

oh and just consulted my IMR Brown Sheet, the max charge listed for a 80 grain bullet with 3031 is 39.5 grains...

work up as always, just in case...

but all three are accurate....

30 grains of 4198 also makes a good off season plinking load...

I did notice that gun likes to be shot cool. A warm barrel prints loads inconsistent. It also seems to like to be fouled pretty good. I have about 50 through gun when it showed the really good groups with the 4064. I may start shooting 3 shot groups as I usually do with sporter weight guns being this rifle is so finicky.
I think that 4064 is the powder, I will confirm this evening, so now I will start playing with seating depth. The decent groups I was getting was at 2.625 and I will work closer to lands from there. I know that i can seat out to 2.700 and still fit magazine well but getting close to feeling like I am running out of neck length for proper tension at that length? How far do yall seat out bullets and how big a jump do you go while testing seating depth?

Thanks

HeavyBarrel

I'm not so scientific with it...

Been working with my ADL lately...

I just make a dummy round...seat it long, and then ram it home in the chamber single fed...

that gives me what the throat length is...

put that in the press and adjust down until I touch the bullet.. then turn the seating adjustment down a hair and call it a day...

and leave the dummy round in the die box for reference, until I'm changing bullets...

I usually buy the TNTs in the larger box with 750 bullets...
and I have a couple of those... so I'll be shooting the TNTs a while...

75 grain HPs seem to be pretty close.. I'd buy those instead if they came in the boxes of 750...

Will your dummy round fit in the magazine box? Is there enough neck tension??

Thanks

HeavyBarrel