From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Newsgroups: rec.guns
Subject: Cleaning .22 LR Rimfire Barrels
Date: 7 Mar 1994 18:32:52 -0500

There's a really neat thing on the market for removing lead from
barrels.  Sold by Kleen Bore, they're 1-in. square cotton patches
impregnated with come chemicals.  Sold in boxes of 25 for about
$2.40, I got a box and tried them.

My smallbore match rifle had been cleaned quite well with Hoppe's
No. 9 solvent, then the bore wiped dry with patches.  Leaving a
film of No. 9 in the barrel for an hour did not dissolve any more
lead that could be picked up by a cleaning patch.  So, it appeared
squeaky clean.

I usually run a benchrest bronze brush through the barrel from
breach to muzzle direction only a couple of times about every
500 rounds.  I had done this in the cleaning process used.

Then I takes one of these Kleen Bore lead removing patches, puts
it on my nylon jag, and slowly pushes it through the bore.

To my surprise, it came out black!  I reversed the lead removing
patch on the jag, then pushed it through again.  This time, it
came out gray in color.  It must have removed something that the
standard procedures did not get.  I then put another one through
but it didn't show any discoloration indicating the bore was more
or like the fuels most cars use these days; unleaded. 

To verify the blackening was not due to chemical reaction with 
the blued bore, I took another lead removing patch and rubbed in
on the barrel's outside; no color change.  Seems to prove that
the one that went through the bore did remove the last microinches
of fouling.

I would guess these Kleen Bore lead removal patches would work in
any barrel to remove all the lead.  

BB  

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: Cleaning .22 LR Rimfire Barrels
Organization: Hewlett-Packard Fort Collins Site

Mike Beck - Leeds University Rifle Coach (bmb5meb@bpxtal.leeds.ac.uk) wrote:

: We clean our .22 match rifles at the end of
: every term (3 times a year) so that they're
: clean when they're not being used
: over the holidays.

My smallbore rifle has about 2000 rounds of test-fired shots through it.  In
a local, 100-yard indoor range, many tests were done to determine the rounds
to be fired to foul the bore enough to start opening up the groups.  I used
Tenex, Temp, Olimp-R and R50 ammo.  With each ammo type after about 120
shots, 100-yard groups would start opening up about 1/4th to 3/8ths of an inch
at 150 shots.  Then the barrel was cleaned.  About 3 to 5 fouling shots were
needed before the groups would go back to their 5/10ths to 7/10ths inch
size.  15-shot groups were used for each test.  After this scenerio was
repeated dozens of times, that convinced me that the barrel should be cleaned
after about 100 shots if peak accuracy is desired.

In tests at 25 and 50 yards, increases in test group sizes were barely
noticed.  Groups at 50 yards would increase in size just enough to be seen.
At 25 yards, I could not tell any difference after firing 300 shots.  I would
hazard a guess that at 50 feet (or less), accuracy degradation may never
be noticed even after thousands of rounds are fired.  Which makes sense to
me as the bullet is in flight only about 1/8th as long as it is enroute to
100 yards; there's not enough time for an unbalanced bullet to move any
significant amount at right angles to its flight path in only 50 feet.

At first, I would use a bronze bore brush after about every 500 shots.  When
I started using Kleen Bore lead removing patches after 500 shots or so, my
test groups were a tad smaller than before.  I stopped using these patches
and went back to using bore brushes; test groups got about 1/8th of an inch
bigger at 100 yards.  After going back to using Kleen Bore patches, test
groups got smaller again.

After talking with some of the top smallbore shooters in the USA, they
told me my test data was very normal with what they have noticed.  Frequent
cleaning is more important at the longer ranges.  At ranges less than 50
yards, it may take thousands of rounds test fired from machine rested rifles
to note group sizes increasing after 100 to 150 shots are fired.

BB