Any body experienced a loss of accuracy in their hmr or mach 2. Got an idea that I'l explain if i see that my loss is common or due to my deteriorating eyesight.
Any body experienced a loss of accuracy in their hmr or mach 2. Got an idea that I'l explain if i see that my loss is common or due to my deteriorating eyesight.
My experience in accuracy loss was cured with cataract surgery.
I suggest that you have your eyes examined to see if that could be your problem.
Ok so much for the drama. I have noticed a decrease in accuracy from my cz .17 mach 2. it always shot best with remington bullets. didn't like hornady or cci. now doesn't shoot less than i" at 50 yds. I have always cleaned it the same way that i cleaned my 22's. i studied the bore and it has raised rifling like a center fire rifle not like the flat rifling in a 22. Since the bullets for the .17's are jacketed, could i have a copper build up problem, and would it be safe to use a copper cutter to clean the gun. I'm worried about etching or scratching the bore with anything stronger than hoppes. or am I way out in left field.
Copper build up makes sense to me.
I never bought a .17; and I think I may have shot all of twenty rounds of .17 HMR out of three different rifles; so take it for what its worth.
Robert
Hoppe's will slowly dissolve copper fouling. Leave the bore moist with good old #9 for a couple days, and see if after that time whether the patches drag out some robin-egg-blue gick for ya.
Copper fouling is as likely an explanation for accuracy deterioration as any other reason.
I don't paint bullets. I like Black Rifle Coffee. Sacred cows are always fair game. California is to the United States what Syria is to Russia and North Korea is to China/South Korea/Japan--a Hermit Kingdom detached from the real world and led by delusional maniacs, an economic and social basket case sustained by "foreign" aid so as to not lose military bases.
I loose accuracy in my 22 rimfires also and generally a good bore cleaning rejuvenates them.
Fast jacketed bullet in a pretty small bore is a good way to get copper fouling. Clean the bore and see if the accuracy improves.
Silver Eagle
TANSTAAFL
There Ain't No Such Thing As A Free Lunch
- Robert A. Heinlein from "The moon is a harsh mistress"
I have found copper buildup that the eye can't see is enough to mess with accuracy( that's my excuse). Use a chemical solution to remove it. A couple swipes, let stand, couple more wet patches, use a clean patch and look at it: does it have blue/ green on it. Sometimes it takes longer like an overnight soaking after a wet patch.
The smaller the bore, the more susceptible to copper fouling.
Use some Sweet's 7.62 solvent, and FOLLOW THE DIRECTIONS.
"When you can't make them see the light, make them feel the heat." - Ronald Reagan
I shoot a 17HMR a lot at sage rats. I mean 100s a day.
I find that accuracy falls off when the copper fouling build up.
Clean the bore with your choice of copper removing cleaner and I`ll bet the gun will be it`s old self again....dale
Truer words were never spoken! I had never really given it much thought on the rimfire .17's but I have heard that the ultra fast centerfire .17's pushing bullets close to the speed of heat that fouling happens pretty fast and can be a pain to get out in the tight bores. Stands to reason the same is true of the rimfires since they use a true jacketed bullet unlike the .22 lr.
Last edited by 429421Cowboy; 01-26-2013 at 02:59 AM.
Raisin' Black Angus cows, outta gas, outta money, outta tags, low on boolits, but full 'a hope on the Rocky Mountain Eastern Slope!
Why does a man with a 7mag never panic buy? Because a man with a 7mag has no need to panic!
"If you ain't shootin', you should be reloadin' if you ain't reloadin' you should be movin', if you ain't movin', somebody's gonna come by and cut your head off and put it on a stick!" Words to fight by, from Clint Smith
Add to that the super fast burning powder and a medium to high pressure for the caliber and you are at the minimum looking at metal being eroded off by the rifling. Not to mention what is getting vaporized at the base. Almost does not matter if they are true jacketed or just copper plated. The .17's are a true jacketed round. I doubt that a copper washed lead bullet would hold together.
Relatively dirty powders and under performing lubes are not going to help the situation.
Silver Eagle
TANSTAAFL
There Ain't No Such Thing As A Free Lunch
- Robert A. Heinlein from "The moon is a harsh mistress"
Yep my 917 hmr needs the bore kept clean. Couple of hundered shots or so groups open up.
Give a good scrub, one fouler shot groups are good again.
Wipe-Out foaming bore cleaner, let set over-night or several hours, patch out and repeat until patch comes out clean.
Larry
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |