going vertical with a 308

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earl39

Guest
maybe i'm being to picky but having trouble with vertical. shooting a 308 savage 12 f/tr. using varget (45.5gr) and 155 smk's. getting about 1.7 inch of vertical at 300 yds. chrony shows from 2917-2933 using lapua brass and winchester magnum primers (federal match primers seem to do the same thing) harris bipod and rabbit eared rear bag. question is i have almost no horizontal (about 1/2 inch) can the vertical be me or should i look closer at the load or rifle or should i just opt for more trigger time. i do not shoot free recoil. using a luppy 8.5x25. my range is slightly downhill maybe a 40 ft drop over the 300 yds.

any help would be appreciated
gary
 
Another Savage shooter

Your post interests me because I am shooting the same rifle and an almost identical load. I use 45.3 gr Varget under 168gr Sierras.

Best I have done so far is 3/4 inch (vertical) at 200 yds. I am looking forward to replies of some others who are more knowledgable than me . If you don't post your findings and results here feel free to PM me with them.

Mike
 
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Well, that sounds pretty good to me, but when I get verticles, I look at my charge consistancy 1st and also seating depth if not in your rifles sweet spot might be causing it. It's what happens to VLD's for me if they are not into the lands .010 or more.
 
MAGNUM primers?

I would think that standard large rifle primers would be more appropriate for this case size and burning rate.

If the primer isn't the answer than tweeking the seating depth or overall length should help round out the groups.

Then again, when all else fails... some rifles like to be held! So the free recoil method may not be best for this rifle.
 
Have a look at Speedy Gonzalez 'How to reduce verticle' in the Articles section of 6mmbr,

all sorts of good observations that helped me.

John
 
earl39 said:
maybe i'm being to picky but having trouble with vertical. shooting a 308 savage 12 f/tr. using varget (45.5gr) and 155 smk's.
Click to expand...

Have you tried the 175 SMK's? I've shot a lot of the 168's from a .308 but, when we changed over to the 175's the 168's started collecting dust. Not knocking the 155 SMK's but, their a sail boat compared to the 175's. At a COAL of 2.920" try 42.0 to 42.5 H4895, the 175 SMK's with a F210M or CCIBR2, at 2.800" reduce the load to 41-41.5. I've seen several Savage and Remington .308's shoot this combo, the velocity is around 2,620 fps. Good luck
 
Gary,

To me the vertical stringing would seem to indicate you may be fairly close to, but not quite on, a sweet spot or 'node'. You might try shooting a few groups at say, -0.3gr/ 0 / +0.3gr relative to where you are now and see if maybe you're just on the edge. If that doesn't work, I'd try bumping the charge up a bit, perhaps 0.5 to 1.0gr in small increments. I'm on my second 12 F/TR barrel... the management around here doesn't like us giving specific charge weights here, so I'll just say that the only barrel I've ever had that shot well with that low of a charge is a custom tube with a *very* short chamber. Both of my 12 F/TR barrels have responded well to considerably more Varget in Lapua cases than you're using right now.

wnroscoe,

Almost sounds like you haven't shot 155s much ;) Running them at speed (2900-3000fps) levels the playing field considerably.

YMMV,

Monte
 
milanuk said:
wnroscoe,

Almost sounds like you haven't shot 155s much ;) Running them at speed (2900-3000fps) levels the playing field considerably.

YMMV,

Monte
Click to expand...

Your right, I havent shot the 155 SMK's much, there's much better bullets out there unless your talking the 155 Scenars. Since the 155's are the required diet for Palma Rifles, they'll never go away. "IF" you can reach 2900-3000 fps from a 26" 10 twist factory barrel they may look good on paper but like I said, there are better bullets out there.

My vote is still the 175's ;)
 
wnroscoe said:
Have you tried the 175 SMK's? I've shot a lot of the 168's from a .308 but, when we changed over to the 175's the 168's started collecting dust. Not knocking the 155 SMK's but, their a sail boat compared to the 175's. At a COAL of 2.920" try 42.0 to 42.5 H4895, the 175 SMK's with a F210M or CCIBR2, at 2.800" reduce the load to 41-41.5. I've seen several Savage and Remington .308's shoot this combo, the velocity is around 2,620 fps. Good luck
Click to expand...

have shot the 175's and like them BUT wanted to use the 155's. as for your 2,620 fps not sure that will work for 1k. i was shooting 175's at 2750. also since i have a 1-12 twist and 30 inch tube the slightly less recoil from the 155 is very welcome when it comes to shooting 100+ rounds in a day of shooting. old age is setting in and don't like being beat up near like i used too.
 
Consider a softer primer or a match primer. I have found match primers like the CCI BR2 and Fed 210M to really help my loads shoot better at long range. Also tweak your load is 1 tenth increments if you have a scale that is accurate enough. I also suggest you look at increasing powder in very small increment.

2900 to 3000fps is a ideal velocity range to be in so get a chronie and find out where you are.

Neck tension can also play a role. I like the standard 4 to 5 thou of sizing. I don't need to depend on jamming into the lands with that much neck tension.

finally, watch the bipod. Hard surfaces/inconsistent hold can cause a bipod to bounce. Try shooting with a pedestal rest or ensure nothing is bouncing/wiggling. confirm that the rifle/ammo is correct, then go back to the harris.

Do you have one or two 'high' or is it more like a vertical line?

Jerry
 
Check ignition

Sometimes we can overlook vertical stringing caused by eratic ignition. I replace firing pin springs every now and then and check for correct firing pin protrusion. Look for any unwanted rub marks on your firing pin spring and on the pin. Keep the pin and spring lubricated with light oil. Not too much. Certainly check for any gunk build-up in the bolt housing. Also check for consistant primer depth.
Willy
 
I have just not had great success with the Sierra 155s. The 150 matchking shoots way better but is of no value at long range. The Lapuas have shot much better as well. Regards, Bill.
 
ok snicker don't laugh

i think i found the problem, as this is a straight out of the box factory rifle i have looked at everything. barrel was floating free with good clearance altho slightly off to the left. made sure all action screws were tight then loosened the front then the middle screw and action popped into place with barrel going to middle of channel. retightened everything. went to the range today and played with getting on paper again. after getting on and allowing for wind had enough for 1 group. vertical was only 4 inches but wind caught one shot and horizontal was bad. shot a 41 score with a 10,9,9,8,5 wind was gusting left to right from nil to about 6mph this was at 1k so all i can say is the wind is killing me. thanks for all the help guys.
 
Just a suggestion, but try getting rid of the bipod and shoot from a rest. Bipods at times can be somewhat "bouncy", depending on what they are sitting on and how high up they are. I have seen this many times shooting varmints at long range.:D
 
Exhogflyer,

Front rests aren't allowed in F/TR in the U.S. Bipod and/or sling.

Earl,

4" group @ 1k? That should do nicely ;)

Monte
 
after the fix group

this is 300 yard group after i found the bedding problem. group measures .960. hope to improve by playing with the seating and lots of pratice.:)
 

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