back to square one with my new .308

[thomis]

Had another shooting session with this rifle yesterday. I gave the bore a thorough cleaning first, because I didn't do this the first time out and I started out with 7" groups but... they did close up to less than an inch by the end of the session. I posted that here.

So yesterday, I tried 8 different handloads using H4895, IMR 4064 and Varget, as well as two kinds of brass and two different primers. I also tried seating the bullets at different COL's. I was disappointed with the results at one hundred yards. The best group was 2" and they averaged all around 2 - 3" with volleys of three shots using each load. I believe the rifle is deer-ready but I'd like to be able to do much better with it on the bench.

All loads were using the Hornady 150 grain BTSP because I plan on using this to hunt deer with. I'm really not interested in trying another bullet. I don't think it's the bullet preventing really tight groups.

Everything seems to be tight on the mounts and rings. I haven't done anything with the stock except take it off and put it back on before I mounted the scope. Don't know much about "bedding" stocks.

My rest is pretty rudimentary though. But I feel like it is steady enough. I'm using folded towels for both front and rear. I'm currently looking at rifle rests on midway's site. My budget is $50 or less so I am kind of limited. I like this one.

I welcome any comments that can get me closer to sub inch groups again.

 

[Abel]

All loads were using the Hornady 150 grain BTSP because I plan on using this to hunt deer with. I'm really not interested in trying another bullet. I don't think it's the bullet preventing really tight groups.

I do not understand this mindset. Try some different bullets. And you may just need some shots fired down the tube to get her to give you consistent groups. Don't clean it so hard and see if the dirty barrel is giving better groups.

 

[shooter308]

Check the stock screws have the same amount of torque, after that put it out of your mind for now. Sounds as if you may have to many things going on at once. If using Federal or Winchester primers, pick one and stick with it, do the same thing for your brass. For the time being seat every bullet at the listed max length for the bullets you are using. Now we can work your choice of powders, never start at anything near a max charge, work up slowly. I have worked on hundreds of 308 rifles and the Sweet Spot for the 150 grainer’s is around 2850 FPS in 99% of all the rifles I have worked with. Try loading at least 5 rounds exactly the same, then increase the powder charge a small amount and load 5 more exactly the same. I have used this procedure successfully many times. You should see something you like by the time you have loaded and fired 60 to 70 rounds. Do clean after each group, take one round of factory and fire it before your start the next group and GOOD LUCK!

 

[thomis]

will do

Abel, I will look for another bullet to try but I'd really like to stay with 150 grains and a BC of at least 0.35

 

[thomis]

Shooter308-
Interesting. So the Hornady bullets I am using list a COL of 2.735". I figured that was a minimum because when I put a bullet in a semi- sized, semi-tight case and chamber it, then measure the COL, I get 2.79". So 2.735" would be 0.055" off the lands, correct? This seems like a lot to me.
As for the velocity, when I chronographed my first few loads, the ones that reached 2850 fps were at the max charge load. I started at the minimum.
I'm curious about the part you mentioned using a factory round first, then trying the handloads.

 

[thomis]

I went back over everything and found a stripped stock screw. The one right behind the trigger guard. This has to be a major cause to accuracy issues. I believe this is the time to return to Savage or is this a gunsmith fix?

 

[Omaha-BeenGlockin]

Easiest thing to do is experiment with bullet weights.

I'll tell my same ol story again:

Browning A-bolt .270

130 grainers--shotgun pattern I'm talking 5-6in groups--almost dumped the rifle right then and there.

150 grainers--better---getting 1-2in groups

140 grainers---one hole shooter-literally-----guess which bullet weight I stuck with?

 

[Afy]

Thomis: The screw at the rear of trigger just holds the trigger guard in. Just replace it your self. Its the two screws in the front that matter.

Is the barrel fully free floated? Try different bullets and seating depths.

Also try KG1 and KG 12 to really effectively clean the barrel.

 

[juk]

I do exactly what shooter308 does. The same bullets, cases, powder and primers. Just adjust the charge weight. I went from the min to the max loads in 1 grain increments, then fine tuned. Bullets were seated at a consistent depth on all loads. After fine tuning the charge weight, I played around with bullet depth. These were with Hornady cases, IMR4064, CCI primers, and Sierra 165 SPBT. This was my actual chart I made as a starting point.


38grn IMR 4064, 1.99"
39grn IMR 4064, 2.77"
40grn IMR 4064, 3.32"
41grn IMR 4064, 2.31"
42grn IMR 4064, 2.57"
43grn IMR 4064, .98"

After fine tuning the charge and bullet depth, groups are averaging in the .8" range for five shot groups. I'm perfectly happy with that, considering it is a hunting rifle and not a BR rifle.

 

[jmr40]

You should be able to replace the screw yourself, but if the screw is stripped, I'd be concerned about the threaded hole in the action as well. I'd have a Smith look at it or return it.

Also the front and back screws are the important ones. It is the middle screw that only helps hold the trigger guard in place. Many rifles only use 2 and skip the middle one altogether.

 

[JDGray]

That rear screw is just that, a wood screw. The action screws should be called bolts, and are not screws at all They should be torqued with a torque wrench to 40-50 inch pounds or so. Good advice on the handloads above, don't change too much at a time, .308s will be plenty accurate with many different powders and primers, bullets making the most difference. Your gun may despise the 150gr lunch your feeding it

 

[Coltdriver]

Try the optimum charge method and make a set of rounds each with a one or two tenths difference in load and shoot them at 200 yards starting with the lowest powered round. I load so that the high end load is the high end recommended by the book.

They will walk up the target. When about three of them group you will have found the sweet spot for that bullet/powder/primer/brass combo.

I did this with a pencil barreled Ruger M77 and it dialed right in. The load that was the best repeats over and over. And its crimped! Because its a magazine feed I could not begin to get the bullet close to the lands like I do with my single shots.

If you google optimum charge method or Audette ladder method you can get more detail.

Edited to add this: Saw Dakotasin's comments and thought I'd add I am using a 165 grain Hornady interlock. My optimum load is Varget, 44.4 grains. Not the hottest load with Varget but outstanding accuracy.

 

[dakotasin]

thomis - i think you got too much going on, making too many of the wrong changes and not enough of the right changes.

i don't know why you're married to the 150 hornady - it is a good bullet, but so are many others. you can probably find no single greater accuracy improvement than the bullet itself. i would encourage you to try some 165 grain bullets. you will find, imo, the best mix between bc and velocity in the 308. my own 308 hunting rifles all use 165 hornady btsp's, and my brother in law really likes 165 fbsp's in his 308.

for your seating depth, what the book calls for as a max is probably off for all factory guns. ignore what the book says and find your rifle's max. start by seating a dummy to max length that will still function in your mag box. chances are good that is your max col. if it is not, then continue to seat shorter until you are no longer engaging the lands.

suggest you try a different bullet, stick to a single brand of brass, a single brand type of primer, and re-try varget, and look at rl-15.

developing an accurate load for a 308 bolt gun shouldn't be a complex process, so don't try to make it too hard.

good luck!

 

[velocette]

With respect sir, you might try the Federal 150 gr ammo that WalMart sells for $13.95 / box of 20. It shoots mighty good in my DPMS LR 308. Usually about an inch or less at 100 yds. The only way to beat is was with handloads & 168 gr Sierra HPBT bullets.\YMMV

Roger

 

[Txhillbilly]

Is your barrel getting copper fouled easily? If so,you just need to get the barrel broken in good.
I have a new 25/06 that is giving me fits.I have followed my usual breakin routine with the barrel,but it's still a copper fouling SOB. I just keep on cleaning and scrubbing the barrel,and have hand lapped it twice.

Sometimes,it just takes a while to get them to come around.

Like others have said,don't just be set on one brand/type of bullet.Your gun might not ever shoot them very good.

My 25/06 loves shooting 100gr bullets,but 110,115,117 grainers have been way off. It has shot some 120gr bullets pretty good though,I just have to find what it likes powder wise.

Don't put too many changes on the table at one time.It just makes things harder to figure out.

 

[NCsmitty]

165gr bullets are a good compromise for 308 or 30'06, good BC and SD, they might be what your rifle needs.



NCsmitty

 

[thomis]

Ok, you all have me talked into trying another bullet. I will listen to the wise advice.
Thanks very much.
thomis