accuracy 22.250

[JB1]

Hi folk,

 

my first post, so please be gentle with me

 

been reading a few posts on here about various topics, all very interesting.

 

now then to my little problem, hope someone can help.

 

I reload for a sako 75SS heavy barrel in 22.250, i use redding compo di set, and have the nickle bush and use nosler brass, scales are RCBS.

 

now the problem i have is the accuracy seemed to drop off a bit with my last lot of reloading,and i cant understand why,

 

would the amount of neck sizing have that effect or not ???

 

i was getting 10mm groups at 100yds but now its opened up to about 13-15mm.

its a bit confusing because all the other measurements are the same as before powder weight AOL and seating depth,

 

thanks

 

jb1

[Guest varmartin]

Hi, and welcome to the forum...

 

If you have suddenly changed the neck sizing it certainly can alter grouping.

Let us know what changes you have made.

 

Also..

Give us a run down on your barrel cleaning regime ....

Not suggesting its incorrect or lacking...but its a good place to start ??

 

Martin

 

ps..I also have a Sako 75 VLS but in .223 /1~8 twist.

[JB1]

i clean using butcher's and plastic brush to actually put a coating of BBs in the barrel, then leave it for about 10 minutes, then use patches to push through until they come out clean. this is done about every 100 shots on average, or when accuracy starts to go off.

 

I dont use the brush for scrubbing , not on an regular clean any way,

 

I will check out the neck size

 

thanks

[Guest 308Panther]

Welcome,

Any idea on the number of rounds that have been run thru it?

It may be time to start thinking about a rebarrel if your that

concerned about accuracy. 1/2 in groups at 100 yrds isnt all that bad....

Yet. But it will get worse as you use it more.

If your unable to trace the problem to your reloading equipment/procedure

this may be the next area to look at....Or it may even be as simple as having the

crown of the barrel looked at by a professional smithy and having it touched up.

 

Hope this helps.

 

308Panther

[6mmBR]

With your cleaning regime, it may be a carbon build up in the throat area which could do with a bit of a bronze brush, especially since you clean every 100 rounds. I shoot a .22-250 Ackley Improved and she gets a thorough clean every 25 shots with a bronze brush and patches to keep peak accuracy.

On the reloading side is it a different batch of powder as lots vary slightly, it may just mean you have to vary the powder charge slightly to bring her back on song. Is it a different batch of bullets or primers, these variables can all have an effect on accuracy.

Cheers

Dave

[Vermincinerator]

JB,

22-250 cases are notorious for stretching with all that stretch going into the neck area.

Even when using Redding Comp Bushing Dies, if your necks are different lengths this will have a direct effect on neck tension.

Trim your cases to ensure consistant neck tension buddy.

 

Ian.

[JB1]

thanks for the replies will have a look at the issues above.

 

i do always trim the cases and check each case for uniformity, though i have bumped the shoulder back on the last load due to exessive pressure to close the bolt. I will go back to basics i think.

i cant see it being the barrel being worn as not put that many through it.

 

I have 3 loaded left from the most accurate load i did so what i will do is strip them and accuratly measure all the variables, and check against the latest loads to see if there is a difference there.

 

All this is to do with a fox ive been after that quite happliy sits at about 300yds and will not budge whatever,

tried it all, its been shot at before so is wise to calls and cant be baited due to other issues.

 

so i need to be spot on with accuracy.

[Ronin]

Echoing what others have said, if your loads are all consistantly the same, I think your barrel requires more frequent cleaning - my 22-250Ai needs cleaning every 30 rounds - and thats with moly coated bullets.

 

it averages .3" at 100 before 30 (or so) and .5 shortly after.

 

I guess that the test groups were shot in still wind and off a solid rest (to take human error out of the equation)?

[JB1]

Echoing what others have said, if your loads are all consistantly the same, I think your barrel requires more frequent cleaning - my 22-250Ai needs cleaning every 30 rounds - and thats with moly coated bullets.

 

it averages .3" at 100 before 30 (or so) and .5 shortly after.

 

I guess that the test groups were shot in still wind and off a solid rest (to take human error out of the equation)?

 

yes all my test loads are shot off a bipod and rear bag, i will address the cleaning issue nest day off and try again with the duplicate load from the 3 remaining original i have left.

[Guest varmartin]

Have to agree to ...100 rounds is stretching it quite a bit .

 

Dont change anything yet....just give it a good soak and dont be scared to get your brushes out...

 

Then try again and see if the accuracy returns.

 

Martin

[Alycidon]

I am a full barrell clean after about 10 rounds, top limit is about 30 rounds.

 

A