i have a friends .243 win. im trying to get a good load It is a mossberg 100 ATR. i am loading 100 gr sierra SPBT. with 4350 So fare it is not grouping good. it is almost to the point of spraying ammo. some are worse than a 3" group.. before i go any futher any suggestion.?

If for deer hunting try a 85-95gr bullet.
And check the bedding and crown.

check the bedding to see if it's free floating....if not, make it that way!

You're not going to solve the accuracy problem that bad by reloading!

i tried all that. i even reset the stock bolts.. I did not know the gun shot that bad when he brought it to me. he sent with it a box of federal premium 100 gr spbt. the same thing i am loading. no good. the only thing i can check now is the scope. but it is a nikon pro staff. 3x9x50 every thing is almost new..

quote:

Originally posted by vines:
i tried all that. i even reset the stock bolts.. I did not know the gun shot that bad when he brought it to me. he sent with it a box of federal premium 100 gr spbt. the same thing i am loading. no good. the only thing i can check now is the scope. but it is a nikon pro staff. 3x9x50 every thing is almost new..

How does it shoot w/ the factory ammo? I always try to shoot a box of high grade factory ammo through a new rifle for a benchmark. If the bedding is sound, look very closely inside the action area, & the scope & mounts are sound, & there is nothing obviously wrong w/ the bbl, like crown damage, then it should shoot decently w/ good factory ammo.
I had my long time fav 338-06 start flinging strays, like from sub moa to 2"+. I checked everything twice, then had it apart for some serious cleaning & found a hairline crack in the front action lug. Had it glassed, added a glassed steel cross bolt, just in case, it's now back to where it was, an honest sub moa rifle.
SOme rifles don't like some bullets. That same accurate 338-06 just will not shoot any 225gr bullet worth a crap at the vel it should run. Shoots 200-210gr & 250gr under 1" w/ good l;oads, but nothing I try will get the 225gr to shoo better than 2" unless vel drops so low as to not be worth the effort.

The best loads in the two 243's I had were 40 or 42 gr of IMR 4350 over either the 100gr Sierra Spz. or the 95gr Nosler Partition.

N E 450 No2... the load i started for this rifel was 41 grs of IMR 4350 WLR primer with 100 gr. sierra. i figered this load would give me a place to start, at least a 1.25" group

fredj338: the factory ammo shoots about the same. almost 3.5" to a 4.0" group..

like vapodog said: I dont think it is the ammo or the handloads..

quote:

Originally posted by vines:
It is a mossberg 100 ATR.

So, what's the problem? A 3" group from this gun and its Chinese scope earns you bragging rights.

Check bore for fouling. Dismount the scope and check the base/bases and rings. Remount a different scope and re-test w/factory loads in two bullet weights.

quote:

Originally posted by vines:
N E 450 No2... the load i started for this rifel was 41 grs of IMR 4350 WLR primer with 100 gr. sierra. i figered this load would give me a place to start, at least a 1.25" group

fredj338: the factory ammo shoots about the same. almost 3.5" to a 4.0" group..

like vapodog said: I dont think it is the ammo or the handloads..

It may well be a 3moa rifle. They are not known for high end bbls. I wouldcertainly verify the action bedding thoroughly, you can try another scope, but I doubt that is the issue on a light recoiling gun like ther 243. I don't even want to bring up skill level, but you did yo have someone else shoot the rifle?

quote : ]did yo have someone else shoot the rifle?
fredj338 usually if a gun that will shoot .750 groups, with my bench rest set up at home i usually can put them in there pretty good. I am shooting my .260, 7MM-08 & .308 in less than 1" at 100 meters..

I had a similar problem with a friend's 243 M700. Turned out he hadn't cleaned it in a coon's age. Shot fine after a week of cleaning!

quote:

Originally posted by vines:
quote : ]did yo have someone else shoot the rifle?
fredj338 usually if a gun that will shoot .750 groups, with my bench rest set up at home i usually can put them in there pretty good. I am shooting my .260, 7MM-08 & .308 in less than 1" at 100 meters..

Had to ask. I've seen many shooters compalin about their rigs & shoots fine when I try it.
again, recheck the action bedding, makes sure it is snug & you have no play in the action. Even snug bolts will allow movement of a poorly bedded action.

What Stonecreek said...

And,

I have been suprised lately on how much the choice of powder has a bearing on accuracy. Previously, I would use a powder that gave me the velocity I wanted and then try different bullets to find the most accurate.

I have since learned from experience that the choice of powder is about as important as the bullet.

If the rifle won't shoot any of the bullets you have chosen with the 4350, try switching powders. Try a different powder with a burn rate similar and maybe one slower/faster.

Try different bullets, that often makes a difference, sometimes huge.

I tried to get one brand of bullets to shoot in a friends 7 Mag, tried two typical good powders got no better than 5". GAG! Tried a different brand, took no time to find a sub-MOA load. Had a simular experience with my own .243 but not as drastic even tho I had to try five different brands/bullets before I got one that shoots well. And then the maker dropped that line! That sort of thing happens with NO predictabilty and that's why I'm not mentioning the brands.

Could also be the trigger pull is too heavy. Also check the bedding, all the stock screws and try different brands of factory ammo.

well, its not the scope, tried another one. not the bases, cleaned it again. tried 4350 & 4831 loaded hot and mild. it is all the same group. well i wouldn't call it a group. it looks like buck shot hit the paper. about 6 or 7 in. group.

The 1-10 twist bbl may shoot better with this. Sierra 85gr HPBT Gameking with IMR 4350 - 42gr., CCI BR2 primer. Rem or win brass. If you cant get at least a 1 1/2" 5 shot groups with this load, you have a bad barrel that will never shoot. Its all in the barrel.

dont blame the mossberg barrels. My 06 mossberg will shoot 3/4s of an inch at a 100 with loads it likes. Many others get comparble accuracy. You sure cant judge a rifle by one load and one bullet. Buy yourself at least 3 differnt powders and 3 differnt 100 grain bulles and try every combination with them and id bet somewhere in there your going to find an accurate load.

i have been loading for about 30 years. i have never shot anything this bad. i have shot 3 different loads at one time in my 7-08. to use them for fouler shots that shot better than this. you would think the worst load you could load would at least shoot 2 to 3" groups.

Is the stock touching anywhere?? If there is a pressure point, is it indeed a pressure point and doesn't come and go as the barrel heats?
Take a look at the crown.
Has anyone talked to the factory?

If he has excessive headspace, which is common on budget priced rifles, full length sizing is aggravating the problem.

Here's a trick that works for me. Try adjusting the sizing die up until you have a 1/16" bulge on the neck of the brass. Bssicaly, you are adjusting the dies to resize all but the bottom 1/16" of the neck. By adjusting the dies as mentioned, you eliminate the headspace problem. The brass is fire form fitted to his rifle, the bullet stays in better alignment with the bore, and you will get tighter groups.

I had a .243 that went from 2.5 moa to .6 moa with that technique.

Did the owner say if the rifle ever shot good? I have read a couple of posts in the last 6 mos. where guys had mis-marked barrels. One was marked .270 Win and was actually a 7mm barrel chambered for the .270. These were factory guns. You might try slugging the bore to check.

If I read all these suggestions and the many attempts Vines took to get better groups, I should say the barrel is the victim. It seems to be a Monday-morning barrel.
Try to shorten the barrel by an inch or one and a half and see what happens. Don't forget to polish the crown. If it turns out to give no better results, get another barrel.
Jan

I use the same bullet backed by 43 grains of varget puts them in the same hole till the 5th shot which flies 1/2 to 3 oclock that was the first handload i tried in it . the factory ammo grouped about 2 inches at best . it is a tikka t3 though not the same gun.

Posted 12 July 2010 14:42 Hide Post
I use the same bullet backed by 43 grains of varget puts

rick boggs, Is that not real hot? 43 grs of varget with 100 gr. sierra. my max load for that is 33.7 grs.. Im showing 44.0 grs with a 58 grain bullet.. im showing 44.0 grs max of imr-4831.

Your 1-10 twist barrel may do better with a short bullet. In 100grs, look for flat base, round nose. Remington rifles have a 9.25" twist and can handle the longer bullets, BT & Spitzers better. Like this Bullet

quote:

Originally posted by vines:
Posted 12 July 2010 14:42 Hide Post
I use the same bullet backed by 43 grains of varget puts

rick boggs, Is that not real hot? 43 grs of varget with 100 gr. sierra. my max load for that is 33.7 grs.. Im showing 44.0 grs with a 58 grain bullet.. im showing 44.0 grs max of imr-4831.

sorry you are right i miss typed bigger keyboard it is 32 grains

just talked to MOSSBERG in Eagle Pass Tx. They want me to sent the gun back to them to see why. update later.

Vines, I had a similar problem with my son's ATR in .270 Win. 3-4" groups.

There was a tiny spot on the left side, just in front of the receiver where the stock was rubbing on the barrel. It was no more then a 1/2 inch long. I sanded that out, and now it shoots under an inch.

talked to Mossberg friday. they are replacing the barrel. will let you know how it shoots when it gets back..

i just got my .243 back on friday 8/13. Mossgerg said they were late getting barrels in stock in the .243 Well, anyway mossberg sent my the target they said was shot with my gun. They photoed the box of ammo with it. it was 100 gr. win. power-point. shot at 50 yards. I measured it to be right at 1.75" group. I have been shooting this weekend and i finally got 1.88" group at 100 yards. That was with 100 gr. sierra btsp. 41grs imr-4350. But, i am getting a flyer to pull off about 2.5" from the center of the group.. Better than a 6" in group it was shooting.

Vines, I'd try a different bullet as 243winxb said. Something like the Speer 100gn BTSP or grandslam in that weight category. I've loaded for a mate in .243 and we couldn't get the Sierra to group, the 1 in 10 twist just wasn't enough for that longer bullet even when we tried pushing them above max.

I tried those powders in my 243win and they didn't work well .
I loaded some H-414 and now it looks like I have a shooter with both 65gr and 90gr bullets.
Have not done any bullets heavier yet.

414 is my favorite 243 powder. Ive found that generaly it does best with a ww primer and a compressed load. My favorite 243 bullet sorry to say is the 100 sierra flat based spitzers but the nos ballistic tip 100 and the speer 100 spitzer have also done great.

Some .243s do not shoot heavier bullets well. Drop down to something in the 70 to 85 grain range and see how it does. Also, try different powders. I have found Varget to work well in the two .243s I've owned. As for the gun itself--what does the crown look like? I have found that an errant crown can really play havoc with groups.