Proper sight in/accuracy test

[ajvigs]

With it finally somewhat cooler down here, its time to drag out my 7mm08 and test all the different ammo I have aquired. .

With that being said, what do you all say is the proper way to test each load and see which one shoots the best in my rifle? Shoot a fowler, then groups of three with a thorough bore cleaning in between each different load?

 

[Guy Miner]

You'll likely receive all sorts of advice, and all of it good. There are some set rules about benching the rifle, eliminating all human input, making it a true test of the rifle and ammunition....

That said, I sling up and shoot it like I would in the field. Prone, sitting, kneeling & standing. If I can shoot it well on the range, I take it hunting. My way is a little different, but it works for me.
.
Regards, Guy

 

[Elkman]

First I would make sure the rifle is reasonably sighted in. I like my test loads to at least be near the bulls eye. I would clean it and fire a couple of shots prior to testing the ammo. I use a large piece of painters paper with the small orange sticky dots for aiming points. My frame is a wooden pallet, so I have at least a clean 3 foot square area. I would put six aiming points well spaced out. Then after shooting label each shot string, so that later there is no doubt as to which was the better. This kind of testing I do off of a bench. When my testing is complete and I am satisfied, I practice using field positions as does Guy.

 

[TRIC]

What Guy and Elkman said. I use my own version of a "bench stabilizer" to get into the bull at the range I want. Then shoot off hand in various positions. 300 yard "minute of paper plate" off hand has always done the trick, if I have done my work off the bench correctly.

 

[Dr. Vette]

I set up, shoot a couple of fouling/sighting loads with one of the types of ammo, then go ahead and shoot from the bench. I figure that each one deserves its own full effort at accuracy and not to be screwed up by my form.

Each one gets its own target, or I sometimes make my own as Elkman says. I time them and put 3 minutes between each shot, 5 minutes between types of ammo, and don't clean between them at all as it's just going to screw things up. I do this at 100 yards, as if they're not accurate at 100 they sure won't be good beyond that. Those that show promise then get shot at 200 yards, often the same day as the rest of the test.

 

[ScreaminEagle]

I used to do the "clean, fire fowler, then three shot group" thing. I've since found that a ladder test is the only way to go. It save on supplies and helps you quickly find your perfect load.

You will have to play around and see how fowling affects how your rifle shoots.

My 7mm-08 likes to have three fowling shots before it settles down
My 280 has to have a clean barrel
My 223 needs almost 12 fowlers to calm down
My 22-250 shoots little holes whether its clean or been shot 100 times!

They are all different

 

[ajvigs]

I used to do the "clean, fire fowler, then three shot group" thing. I've since found that a ladder test is the only way to go. It save on supplies and helps you quickly find your perfect load.

You will have to play around and see how fowling affects how your rifle shoots.

My 7mm-08 likes to have three fowling shots before it settles down
My 280 has to have a clean barrel
My 223 needs almost 12 fowlers to calm down
My 22-250 shoots little holes whether its clean or been shot 100 times!

They are all different

Can you explain this ladder test for me?

 

[ScreaminEagle]

It's when you load a single round for each charge increment. Lets say you want to test a load for your 280, so you load from 52gr to 55gr in .5gr increments, a single round each. Go to the range. 300-400 yds is best depending on caliber, though I've done it at 200yds. Shoot each round at the bullseye. When you check your target you will notice a vertical stringing, due to different charges of powder. You should find a group of three or so charges that have almost no vertical stringing. This is your guns sweet spot.

 

[usmc 89]

The shooting three and cleaning will not provide the information to your accuracy question. The first shot down a clean barrel will be likely 70 fps slower than a fouled barrel, second shot 30-40 fps slower and so on until the barrel is fouled and consistant. I have done this through my chronograph several time with multiple calibers and the results are consistant. I would assume your 7-08 would handle 100 rounds or more before fouling compromised accuracy. I have shot several matches with my .284 win and 6x47 lapua where the round count was 60+ rounds fired without cleaning and accuracy was still excellent. As mentioned above some rifles take a few rounds before they settle in to begin with. I will usually run five through mine before i try to group or hunt with them.