Primers and accuracy

[Tomekeuro85]

I currently shoot 2 guns, .223 and .308. My 3-4 shot groups are awesome, usually under .5 moa with both stock guns. The problem is that one or two bullets go wherever they feel like going, ruining an otherwise good group.

I use all good components except primers. I just use standard CCI primers. I could have a .4" four shot group and the fifth (not always the last shot but somewhere in between) opens it to .9" or something stupid like that.

Could the primers be the cause for these flyers? Or is it something else? I weigh brass, bullets, powder is consistent, brass is uniformed, etc. They only thing I do not control is the primers.

Please help because this is driving me crazy to know if I can place one more shot where I want it to go I can have a sub half moa rifle. Instead, it averages out to about .7" at 100. Both do actually.

 

[YellowLab]

Magnum primers will definiately change things.

I'm sure that there are some variance in energy output, flame pattern, anvil hardness between the various manufacturers... plus now there are supposed to be lead free primers that are hotter than normal leaded primers.

Just like when you were 'figuring out' your loads.... try it and see. 100 primers are less than a buck, take notes and find the brands your gun likes.

 

[dakotasin]

the probability of your primer causing the fliers is low. really low.

i would hazard a guess and say it is more in your shooting technique, than in your load. eg, does your rifle like to be leaned into hard? does it prefer a very soft touch? how about when you are steering it into position - is that producing torque on the stock? how about your shot timing - is it consistent? do you let the next round cook in the chamber while you are waiting for your next shot?

i have a 700 lvsf... it honestly does not care how it is held, or pressure on it - shoots about the same. i have an ar-15 that needs lots and lots of downward pressure on the butt of the stock to shoot well - but it will outshoot any other gun i have (except my 1000 yard gun) at any range on any day as long as i am feeding it appropriate ammo, and have very little weight on the bipod...

 

[Steve C]

There are so many variables interacting with each shot, some of significance and others of little effect. Regarding the accuracy potential of ammunition, the bullet is the most significant factor. Then there's the shooter which as a biological organism is in constant fluctuation from respiration, circulation, environmental inputs and mental concentration. Add in factors from wind, barrel heating, etc. its a wonder that you can get any 2 bullets to cut the same hole. Those rouge rounds that open up your group can be from things not under your control. If you're getting sub MOA be happy as few rifles and shooters can do that without a lot of practice and work.

You want to see groups open up, just get into some competition where the added stress will open them right up. That's all shooter and not the ammo.

 

[USSR]

I agree with dakotasin. 3 shots tests the rifle -- 5 shots tests the shooter.

Don

 

[Dave P]

Your cci primers are not the problem.

How did you come up with that load - trial and error? Consider the Creighton Audette (Ladder) method of load development. This easy method can let you determine a accurate but tolerant load in just a few rounds. A search should reveal the instructions.

DAve

 

[Grumulkin]

I've experimented with various primers. In the case of a 357 Herrett, large rifle magnum primers definitely gave better accuracy than plain old large rifle primers. In a 308 Win. it made no difference. In a 44 Magnum large pistol vs magnum primers, the magnum primers brought on high pressure signs earlier and didn't improve accuracy. You just have to experiment to find out what works with your loads.

 

[AnthonyRSS]

I don't know about standard primers, but my gun cuts .7" three holes with Win LRM primers. Its just a standard Winchester m70 Ranger in .30-06.

 

[Paul "Fitz" Jones]

The Best ever primers

Are Federal and Winchester consistently #1 and #2 and Remington users very seldom complain.
Out of the thousands of reloaders I have sold to worldwide competitors CCI has been consistently the worst and has caused the most explosions in the progressive reloaders in a company I was a distributor for. I have seen some nasty facial injuries.

I have had many thousands of customers over the years and whenever I am told of a failure to fire in a match they are consistently because of CCI primers. I have had this feedback from my customers since CCI was invented. I sold machines, never sold primers.

CCI primers feedback says they can be out of round, varying heights, burrs on the cup tops, cocked anvils and paper slivers from their boxes clogging automated reloader primer feeders. I had to invent a safety blast tube for the primer magazine on C-H Auto Champ machines. Star Reloaders have a stronger Brass Primer magazine. The explosions were cause when a clog or failure to feed occurred and force was used to get the reloader to cycle and one fellow blinded an eye looking down a primer magazine while forcing the operating handle. He sued and I felt it was like lighting a match to look in a gas tank.

I have sold a hundred 1,000 capacity primer turrets to fit on top of Progressive Reloader primer magazines and I always ask for a letter that I will not be held responsible if "against my advice" CCI primers are ever used in my turrets. I just sold my last two on ebay and all owners were warned and I have had no complaints on any of them ever exploding with Federal and Winchester Primers in any hand operated reloader.

Men without progressive reloaders have probably never heard of an explosion and may only have failures to fire and unexplained flyers in their targets.
I know that they are always the cheapest and favored by beginners and some high volume shooters but it only takes a couple of minutes with magnifying goggles or a hand held glass to inspect their cups and anvils carefully before using them for a serious match. Also make sure they are seated fully by feel otherwise there can be a cracking of the primer compound cake if they have to move forward when hit with the firing pin and if hit again may not fire as has happened.

All opinions are based on my reloader customer feedback.