Accuracy drop off after cleaning

[hounddawg]

Ok you got me curious Bart, I went down and gave the CZ it's once a decade cleaning. I cannot recall the last time I cleaned this rifle, at least ten years and 10,000 rounds ago. Maybe more

Pic 1 is of the 12 cleaning patches in left to right order - the top 4 were dry, I followed those with 4 wet with Hoppes 9, that is the middle row, then finished up with 4 dry on the bottom row. From the looks of the borescope pic looks like I need to put another wet patch down and let it soak a bit, some small carbon streaks were left

Pic 2 was taken with my little teslong borescope after cleaning. I did notice some light pitting at the 6 o'clock position of the barrel. That might be the glass dust from the primers that was mentioned in that thread you linked. Whatever it is accuracy does not seem to be a issue. The rifle still shoots lights out if I hold my tongue just right and use good ammo, as witnessed by Pic 3 which was shot back in July 2020. With premium ammo the little $300 rifle can still shoot a .473 average for 25 shots at 50 yards.

Now I just have to get the barrel dirty again before the next ARA match

 

[Bart B.]

Ok you got me curious Bart, I went down and gave the CZ it's once a decade cleaning. I cannot recall the last time I cleaned this rifle, at least ten years and 10,000 rounds ago. Maybe more

Pic 1 is of the 12 cleaning patches in left to right order - the top 4 were dry, I followed those with 4 wet with Hoppes 9, that is the middle row, then finished up with 4 dry on the bottom row. From the looks of the borescope pic looks like I need to put another wet patch down and let it soak a bit, some small carbon streaks were left

Pic 2 was taken with my little teslong borescope after cleaning. I did notice some light pitting at the 6 o'clock position of the barrel. That might be the glass dust from the primers that was mentioned in that thread you linked. Whatever it is accuracy does not seem to be a issue. The rifle still shoots lights out if I hold my tongue just right and use good ammo, as witnessed by Pic 3 which was shot back in July 2020. With premium ammo the little $300 rifle can still shoot a .473 average for 25 shots at 50 yards.

Now I just have to get the barrel dirty again before the next ARA match

What is the biggest group's size?

 

[hounddawg]

group sizes are right there on the target Bart but I'll play - largest group .603 ", smallest .318", average .473".

Anyway the point is you do not need to clean a .22 LR every twenty five rounds and you don't need a $3K gun to shoot .3 inch groups at 50 yards

 

[tangolima]

OP's rifle returned to, not improved upon, precleaning accuracy after 9 fouling shots. That sounds right.

But it begs the question; why do I want to clean the rifle? 9 rounds costs $5 to $10 today. For winning match and breaking record, perhaps. I'd rather put the money somewhere else.

I have a Mossberg 151M that can put all 50 rounds into a hole about 1" big at 50yd. The rifle cost less than $100 and I have cleaned the bore only once in 7 years since I bought it used. I will get laughed at if I bring it to a proper match. But it works more than ok for me. Oh, it doesn't even have a scope, but wears the Mossberg target sight.

-TL



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[Bart B.]

group sizes are right there on the target Bart but I'll play - largest group .603 ", smallest .318", average .473".

Anyway the point is you do not need to clean a .22 LR every twenty five rounds and you don't need a $3K gun to shoot .3 inch groups at 50 yards

Now I understand your reasoning.

You use the smallest test group to define accuracy.

I use the largest test because it encompasses all test shots.

 

[hounddawg]

actually you don't understand. If I used your standard I would judge your shooting career by that 1998 Palma match. I am sure that your average was better than that

I use the average of 25 to 100 rounds to define accuracy of any given rifle, ammo etc for that particular day. Accuracy has many factors, the rifle, the ammo, the shooter and environmentals. No one group of 5 rounds defines the accuracy. I will take three targets of twenty rounds each, overlay them using OnTarget software then use 95% CEP to evaluate an F class match

In any match I shoot take the average of all targets I shoot to evaluate my performance.

Back to the OP Tangolina makes a very valid point

But it begs the question; why do I want to clean the rifle? 9 rounds costs $5 to $10 today.

Now that I have cleaned that CZ it will take me 10 - 15 rounds to get the barrel back into shape. Not that big of a deal with $10 a box .22 but with centerfire ammo costs these days it could get expensive

 

[Bart B.]

It's a very stupid idea to use my 1988 team match score to define the rifle's accuracy because I didn't rest the aperture sighted rifle on bags but shot from prone and the coach gave me sight adjustments as it was a team match shot during 30 mph average cross wind changes across a 10 to 15 MOA spread centered on 30 MOA at the 800. 900 and 1000 yard lines. Issued ammo was arsenal 7.62 NATO M80 ball. First shot at 800 used 28 MOA right.

When properly tested with a scope sight and handloaded Sierra 155's at 800, 15 or more shots went inside 4 inches. That's done a half hour before sunrise when the air is very calm and stable. Started with a clean barrel, 1 and 2 were first two shots.