need some major help!!

[hondaracer408]

my gun it a Tikka T3 tactical .308 11-1" swist and a 20 inch barrel. I have had bad groupings relaoding so i decided to but 3 boxes of Remington premier match 175gr smk. Traveling out of my barrel at an average of 2550 fp.sec and altitude of 1200 ft... Now 100 yrds grouping are great but when i got to like 300 yrd i end up w 4.5 inch groupings..... im shooting off a 6-9" harris bipod and a sand bag in the back.. my scope is tight and rings i checked them several time.. any ideas? or suggestions?.. thanks

 

[Bulseyetom]

That equates to about 1.5 moa which really isn't too bad. Two things come to mind right off. First is parallax in the scope. The second is wind. I never thought much about wind until I started shooting benchrest and shooting over wind flags. It is amazing how much the wind shifts without you noticing it. Without using wind flags, it might be hard to shoot less than 1.5 moa at 300 yards. Tom

 

[fdshuster]

hondaracer408: You're also handicapped by using the Harris bi-pod, if working toward very small, sub MOA groups, at longer distances. I have the same 6" to 9" Harris bi-pod and while very good, cannot compete when compared to using my Sinclair 17# front machine benchrest. I have yet to see a winner in our local benchrest g'hog matches, to 500 yards winning with a bi-pod. Not trying to take anything away from them, they are great for their intended purpose, but they cannot compete with the front machine rest. JMO.

 

[therifler]

Have you tried different torque on your receiver screws ? It sounds like that factory ammo is not to far out of whack .
Also frank makes good sense with reference to the bi-pod .
T.R.

 

[Kenny474]

Like has already been stated, 1.5MOA at 300 yards isn't half bad. And all of the other suggestions have been very good as well.

My question, what are your group sizes at 100yds and for how many rounds? And is the spread of the group at 300 more horizontal/vertical or equal and how many rounds?
Also, have you ever tried shooting at distance before? If you are new to long range, than your technique may need some improvement. Slight differences in hold that won't make much of a difference at 100 will be very evident as the yardage increases.

And as a last point, what kind of scope are you using, and does it have parallax adjustment? Slight shifts in your scopes zero that don't show up at 100 will also be exaggerated as range increases.
As you increase range, anything that is lacking will become more evident in resulting accuracy.

But before you start going over everything looking for fault, use a quality front rest and rear bag and evaluate any improvement that may give. And torque all action and scope screws with a in/lb torque wrench. That way nothing is torqued unevenly.

Remember, 1.5MOA ain't bad to start. Good luck and happy shooting.

 

[Steve Blair]

hondaracer408: You're also handicapped by using the Harris bi-pod, if working toward very small, sub MOA groups, at longer distances.

Frank,

With all due respect, I must disagree. Although it requires more effort and concentration, it is very possible to shoot very small, long-range groups from a bipod. This article on the main site gives some good tips for accurate bipod shooting. The attached group was shot from a Harris bipod mounted on my Pierce .308 and just my shoulder in the back. I was shooting Lapua 155 Scenars over 44.0 8208 XBR. That load stays under an inch at 300 yards, wind allowing.

 

[fdshuster]

Steve: We are in agreement, sort of. Yes, small groups can and are shot with a bi-pod. My son competes in F Class F/TR matches with his Harris bi-pod at 600 yds., and kicks a**, in his class. Matches are fired at the Port Malabar Rifle & Pistol Club just outside Melbourne FL. But to do it properly he had a lot of coaching from some of the best prone F-Class competitors in the area: people who have mastered the requirements and learned to overcome the obstacle's. The most glaring problem is the jumping/torqueing/twisting recoil that will lift one of the legs off the bench. The bullet is still in the barrel when the rifle is going thru the recoiling cycle, and I see that as a major problem that you do not have with a front rest and 2 1/4" and 3" wide forend. Guess that's also the reason there is a seperate class for those using a benchrest type front rest in these F-Class matches. And I have to look at equipment being used in the precision BR matches, like the recent Super Shoot at Kelbly's. Show me at least one bi-pod used there. "Honda" was questioning how to shrink his group sizes and unless he is highly skilled in using a bi-pod off a bench, I see it as one of many possible problems. No better method of supporting a rifle for carry type hunting situations and the before mentioned prone F-Class, but "outclassed" by a front machine rest. As I said, just my opinion, with a little experience in the use of my Harris bi-pod.

 

[Steve Blair]

Well, that is why I have a Farley rest and Edgewood Minigater. I misunderstood that your intent was to say that one could not shoot well from a bipod. Sorry.

The images show my two approaches to similar problems. The 12F has a 30" McGowen .308 barrel and the Pierce has a 26" Bartlein, both 10" twist. Although the Sinclair unit on the Savage is a legal bipod, I would not want to haul it around like I do the Pierce. Without dust covers, the 12F weighs .8 ounce shy of the F-TR limit. It shoots 210 Bergers better than I can.

Frank is correct that the OP should develop a stable bag and rest technique for load development and testing. Even though I have shot from bipods for 30 years, I still have an annoying tendency to introduce vertical if not fully concentrating.