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m1a_scoutguy
09-11-2015, 10:26
Hey guys quick question about my newly installed barrel on my 1903A3. I ended up going full tilt and got a Krieger, BBL was installed and head spaced by Krieger and it is in 30/06. Anyways I'm not having very good luck with it in the accuracy dept ! :icon_scratch: I feel I have done everything correctly,BBL channel is clean & clear and BBL touches only on the front pad,I have even shimmed it a bit for more upward pressure and it kind of helped but no great shakes yet. I checked and filed down the guard screw bushing in the back,installed a milled trigger guard,etc,I really feel I have everything covered,,"but" just not feelin the krieger love yet,,LOL So my question is with this being a New modern day BBL and even reading that some old school bbls did better with total free floating,,could this be my case ? Is it worth a shot to clear it out and FREE FLOAT the whole bbl and see what happens or should I try other things ? I have shot both LC & HXP Mil-Spec ammo with 3 to 4 inch MOA groups and even reloads with all the common powders & 155/168 match bullets. I can post my best target so far if ya want to see,,but not much to look at. I used H4350 168 Nosler,Fed NM primers and once fired HXP brass. Best target is about 2.5 Inch spread. I would expect better from this bbl. I am using a solid rest and have a Leupold 4.5x14x40 scope mounted with a EGW steel mount. Sorry guys don't hate me for being non traditional,my 61 year old eye's stink ! LOL Thanks for any help or ideals.

kragluver
09-11-2015, 11:00
Given that upward pressure helped some I'm betting that your receiver is not well bedded. I read the list of changes you made but it could be that the wood on your stock has shrunk to the point that the recoil lug is not bearing solidly against the wood. Just a thought.

Free floating should work nicely BUT if the receiver is not well bedded this won't fix your problem. Free floating will be a bit difficult with a full military '03.

m1a_scoutguy
09-11-2015, 11:10
Given that upward pressure helped some I'm betting that your receiver is not well bedded. I read the list of changes you made but it could be that the wood on your stock has shrunk to the point that the recoil lug is not bearing solidly against the wood. Just a thought.

Free floating should work nicely BUT if the receiver is not well bedded this won't fix your problem. Free floating will be a bit difficult with a full military '03.

Thank you Sir for the quick reply. I forgot to say I did buy a New 1903 stock from CMP. there is a chance I screwed something up in fitting the receiver/rifle to the stock,but I will look into it a bit more. I have had the darn rifle in and out of the stock a hundred times it seems,,but a few more won't hurt I guess. Thanks again.

m1a_scoutguy
09-11-2015, 11:26
Given that upward pressure helped some I'm betting that your receiver is not well bedded. I read the list of changes you made but it could be that the wood on your stock has shrunk to the point that the recoil lug is not bearing solidly against the wood. Just a thought.

Free floating should work nicely BUT if the receiver is not well bedded this won't fix your problem. Free floating will be a bit difficult with a full military '03.

Thank you Sir for the quick reply. I forgot to say I did buy a New 1903 stock from CMP. there is a chance I screwed something up in fitting the receiver/rifle to the stock,but I will look into it a bit more. I have had the darn rifle in and out of the stock a hundred times it seems,,but a few more won't hurt I guess. Thanks again.

Parashooter
09-11-2015, 11:32
If using an issue-pattern full-length stock, shimming the front end of the forestock isn't a great way to apply pressure, as it's likely to cause undesirable barrel contact with handguard and/or upper band. Adjusting GI forestock tip pressure is accomplished properly by altering the angle at which the receiver sits in the stock, scraping or shimming wood to effect more or less pressure at the forward barrel bearing - while maintaining clearance between magazine box and receiver. Once appropriate pressure has been established, handguard and bands may be installed and checked for clearance. It should be possible to lift the barrel at least .010" without touching the upper band.

The 03-A3 stamped upper band can sometimes be "squooshed" in a vise enough to increase upward clearance significantly.

purple
09-11-2015, 04:11
If you want to increase pressure at the forend tip to the desired 4-7lbs you can insert a washer under the rear tang of the receiver with the hole enlarged to pass the guard screw through. In this way the recoil lug area of the stock acts as a fulcrum and the barrel is depressed against the forend tip. If you want to experiment with free floating you can add a shim under the receiver behind the recoil lug to lift the barrel out of contact with the stock at the forend tip. In either case the top of the barrel must not be in contact with the metal of the upper band. Make sure that there is some clearance between the rear of the receiver tang and the corresponding recess in the stock. If this isn't the case the tang will act like a recoil lug and will split the stock behind the tang.

m1a_scoutguy
09-11-2015, 11:30
If using an issue-pattern full-length stock, shimming the front end of the forestock isn't a great way to apply pressure, as it's likely to cause undesirable barrel contact with handguard and/or upper band. Adjusting GI forestock tip pressure is accomplished properly by altering the angle at which the receiver sits in the stock, scraping or shimming wood to effect more or less pressure at the forward barrel bearing - while maintaining clearance between magazine box and receiver. Once appropriate pressure has been established, handguard and bands may be installed and checked for clearance. It should be possible to lift the barrel at least .010" without touching the upper band.

The 03-A3 stamped upper band can sometimes be "squooshed" in a vise enough to increase upward clearance significantly.


If you want to increase pressure at the forend tip to the desired 4-7lbs you can insert a washer under the rear tang of the receiver with the hole enlarged to pass the guard screw through. In this way the recoil lug area of the stock acts as a fulcrum and the barrel is depressed against the forend tip. If you want to experiment with free floating you can add a shim under the receiver behind the recoil lug to lift the barrel out of contact with the stock at the forend tip. In either case the top of the barrel must not be in contact with the metal of the upper band. Make sure that there is some clearance between the rear of the receiver tang and the corresponding recess in the stock. If this isn't the case the tang will act like a recoil lug and will split the stock behind the tang.

Thanks guys,good info ! I will play around with your ideals and report back ! That's a good ideal to shim the front of the receiver to get the bbl up off the front bed,that should be a easier & faster way to find out if "free floating" the entire bbl will help instead of sanding/scraping the front bed out and then realizing it didn't work ! :icon_redface: I actually had the hand guard and front band off the rifle last weekend while at the range and noticed no difference with it on or off so I feel I eliminated the issue of the hand guard hitting or rubbing on anything, so when I shim the front to free float I will just leave it off and then check and replace as needed. Thanks again guys,its supposed to be a rainy weekend but I'll still make it to the range and report back. Happy Weekend !! :banana100: