C-More losing zero while shooting...

[G-ManBart]

So, I'm rolling along shooting Area-2 yesterday and today. Things are going well, I've shot a clean match and I'm generally having a solid performance. I get to the 8th stage, take a couple of shots, put one way right into the hard cover on the second target, didn't call it there, but it was on the move so I just figured that was why it was right, saw it and made it up. Then I get to a long range popper and can't hit it...the freakin' gun is hitting 6-8" right. Dead center hold, slow press and a clean miss. The problem was worse because of the lighting I couldn't see where the bullets were hitting. I burn through three mags and finally take down the last popper by aiming off the left side of the center.

I go up to the sight in area and sure enough, it's hitting 6-8" right....wtf? This gun/scope has never, ever done anything weird. I checked the scope mount, solid as a vault. The tension screw on the windage seemed tight when I loosened it to make the adjustment. I got it back to point of aim and cranked down the the tension screw, and it was still right on afterwards, but can't for the life of me figure out what the heck happened.

Anybody ever have one do this out of the blue?

Second question, I've been told that the tactical (aluminum body) C-Mores hold their zero better....anybody know if that's generally true or not? I'll eat the 2oz weight difference to never have this happen again! I figured I'd be in a good position to win my class, but after a 53s stage when it should have been 25-27s, I'm probably toast. Fortunately, or unfortunately, some of my direct competion have had a couple of disasters, so there might still be hope, but this is about as pissed as I get when it comes to shooting. I don't mind when I mess up so much, but when my gear lets me down it's a whole different situation.

[Zerwas]

Oh brother can I relate to you!!!!! I haven't had my Cmore loose the zero in the MIDDLE of a match. But, I sure have between matches...happened to me at least 6-7 times this year.

The biggest mess up was at Open nationals this year...

FIRST stage of fire (of course one of the biggest stages of the match) I start out on stage #11 (the one with the longer 4 pieces of steel one of which activated the drop turner for those that remember). Anyway I go after the closer targets on the right side of the course and I plug a tight no shoot and I didn't call it. I shoot it again,,the bullets touch (on the no shoot). I know something is wrong. I go to shoot the long steel thinking I'm going to just burn it down..well, I missed and missed and missed again. I purposley slowed down into my old bullseye mode and really took my time and still missed. I knew from prior experience I needed to "quadrant shoot" to see where my C more was off--again. I started shooting 12" high and 12" right and I heard "BING" when I finally shot the target.

I re-zeroed the C more before going to the next stage of fire. I was told by a squad mate it happens to the plastic C more's with storing them in a hardcase with foam touching the C more. It causes the C more to move INITIALLY, and then after a few hours the C more will go back to it's original zero. Well, this is exactly what happened to me. As mentioned before, I re-zeroed the C more after the first stage at natinals and by the 5th stage, it came back to it's original zero. This was the infamous car stage with the no shoots/targets 35 yards away. I had to aim 12" low and 12" left and I had a very nice grouping on the top of the bottom A zone.

Shooting open division is fun, when I don't have to chase the dot all over the place. I have to admit though it is extremely frustrating when something like this screws up your matches.

This was my 3rd C more this year by the way.....

This is my first "click switch" C more as I heard they were more durable, but you know how rumors are.

So, to get back to your situation which MAY be related to my situation. All I can say is re-check your mounting screws on your C more itself. Be sure you use red lock tite on them.

I wish someone out there could shed more light on this situation as well.

I am all ears....

[shred]

Everytime I've had a C-more lose it, it's been because the vertical lock setscrew has come loose.

I don't lock the windage adjustment and it stays put all on it's own. Never had one of those move. I'd pull the scope off and have a careful look for cracks.

[HSMITH]

I never loosen the lock screws at all and never have a problem with wandering zero. I am on my third C-more in 2 years, but I don't adjust them after mounting them. I have had the scope be off about 4-5 inches at 15 yards straight out of the bag with my old Serendipity, heavy stuff in the bag was pressing on it and bent it until it had 15-20 minutes to relax.

[rupie]

I read somewhere that someone had the lens come loose and track sideways, eventually it fell out.

[G-ManBart]

Well, I went back to shoot my final stage today and it stayed where I put it. I just checked everything I can think of again and all the screws seem tight etc. I'm a bit at a loss, but I guess I'll have to see what happens tomorrow The front mounting screw tightened up a tiny bit when I checked it, but not enough that I'd suspect it would have let the scope body move previously.

Hmmmm...just had an idea for that. If C-More added a locating pin near the two mounting screws and the mount had a corresponding hole, there would be no way for the body to shift even if the screws were a little loose....maybe I shouldn't have typed that where someone can steal the idea...lol. Edit to add "uh, duh, they already have those...it's not the body, but the plate that the adjustment screw moves that matters".

I'll take a couple of sighters in the morning to make sure nothing moved while I was checking it out now and hope for the best. At least I had a decent final stage...nothing like running up to a port and hoping you'll be able to hit the far poppers.

Shred, when the elevation screw was loose on yours, did it change the windage? R,

Edited November 10, 2008 by G-ManBart

[HI5-O]

Everytime I've had a C-more lose it, it's been because the vertical lock setscrew has come loose.

same here

[spd522]

My Serendipity on my Open Para is 12 yrs old and still holding zero. Guess I got a good one?

Actually, none of my other C-Mores have moved either.

Craig

[shred]

Shred, when the elevation screw was loose on yours, did it change the windage? R,

it'll move a little bit in windage due to the pressure of the lock screw torquing the lens just a little side-to-side, but mostly elevation is what changes slowly as that gets loose.

One thing I do is mark on the scope with a marker where the screw slots are when it's sighted in. Makes it easy to get 'close' if it does come loose. I've had a number of C-mores over the years and only one or two have had the loosening-lock-screw problem, and a little purple locktite usually straightens them right out for at least 10K rounds.

[Catfish]

Calamity Jane's C-more's lens fell out at nationals. She had a LOT of trouble hitting steel on the first stage, zeroed the gun, and then the lens fell out shortly thereafter and she switched to another gun.

Is your lens tight?

[G-ManBart]

Shred, when the elevation screw was loose on yours, did it change the windage? R,

it'll move a little bit in windage due to the pressure of the lock screw torquing the lens just a little side-to-side, but mostly elevation is what changes slowly as that gets loose.

One thing I do is mark on the scope with a marker where the screw slots are when it's sighted in. Makes it easy to get 'close' if it does come loose. I've had a number of C-mores over the years and only one or two have had the loosening-lock-screw problem, and a little purple locktite usually straightens them right out for at least 10K rounds.

Thanks. The elevation was still perfect, so it's unlikely that was the problem since it was 8" right at 15yds....ouch. I'll be marking the adjustment screws asap...thought about that when I was checking everything. R,

[G-ManBart]

Calamity Jane's C-more's lens fell out at nationals. She had a LOT of trouble hitting steel on the first stage, zeroed the gun, and then the lens fell out shortly thereafter and she switched to another gun.

Is your lens tight?

It seems to be...just grabbed it and tried to wiggle it around...nothing. R,

[BBoyle]

The only time my C More lost zero is when the body had cracks above and below the windage adj screw. Went from doing 1" groups to 8" groups real quick!

Look around at the body for any cracks, large or small. The rebody does not cost that much and I had the scope back in 10 days!

[wide45]

Bullet touching the comp.

[G-ManBart]

Bullet touching the comp.

Definitely not. There are no marks on the inside of the comp (I've seen it before on other guns) and the bullet holes were perfectly round after I fixed the zero...and some shots were 20-25yds.

[ExtremeShot]

So did you just resight it in by adjusting it to account for the 8" right? ......It might be the bullet hitting the comp. I had a bullet hit the comp and it almost took a magnifying glass and a high powered light down the muzzle to tell. The holes in the target were round as well. As I recall, it was shooting them off to the left about 7". Check to see if the comp is loose or if you have a lot of buildup that might be reducing the diameter of the hole.

Darren

[G-ManBart]

So did you just resight it in by adjusting it to account for the 8" right? ......It might be the bullet hitting the comp. I had a bullet hit the comp and it almost took a magnifying glass and a high powered light down the muzzle to tell. The holes in the target were round as well. As I recall, it was shooting them off to the left about 7". Check to see if the comp is loose or if you have a lot of buildup that might be reducing the diameter of the hole.

Darren

Yes, I adjusted the windage for the 8" and it has stayed put since then. It absolutely was not the bullet hitting the comp. Since the windage adjustment I put about 80 rounds through the gun and it's hitting to point of aim. R,

[psyops]

Chris,

I had this 'problem' with my Bedell and it was my mount screws. The C-more felt tight so I discounted that immediately, but after further examination, I could further tighten each mount screw another half turn. A little red loc-tite, and it was done.

Hope it works out, see you soon.

-Mike Patrick

[G-ManBart]

Chris,

I had this 'problem' with my Bedell and it was my mount screws. The C-more felt tight so I discounted that immediately, but after further examination, I could further tighten each mount screw another half turn. A little red loc-tite, and it was done.

Hope it works out, see you soon.

-Mike Patrick

Hey Mike,

Yeah, I wish it was that simple....lol. I checked the mount screws and they wouldn't budge a tiny bit tighter, so I'm still at a loss. I did notice a slight ring on the windage adjustment screw as if it had rotated against the set screw/tension screw. The tension screw might have been just light enough that it started moving and each shot made it worse. The first shot I called an A and it was maybe 4" right...by the time I finished the stage it was 8"....so I'll mark the adjustment screw position now and see if it moves as I shoot it more. R,

[Silver_Surfer]

G-Man Have you checked the dot module for movement/looseness? Would'nt hurt to try to change it out to see if it may help. Looks like you covered everything else!

[Sandro]

I am having similar issues with mine as well, and it is irritating me to the point where I am thinking about getting a OKO instead.

[G-ManBart]

G-Man Have you checked the dot module for movement/looseness? Would'nt hurt to try to change it out to see if it may help. Looks like you covered everything else!

Thanks for the idea....I did check that as well. I now think that it was slowly shifting starting back about three matches ago. I found a very slight line on the windage adjustment screw that seems to have been left where it contacts the tension/set screw. That line corresponds pretty well with how far off the gun was by the end.

I think it was just moving a tiny bit at a time and maybe hit a point where it made a big jump, all at once, during that stage....it even seemed to get worse as the stage went on...and on...and on!

I've since verified the zero and marked the screw with a silver sharpie so I'll know if it moves. If it does, it's coming apart and some Locktite is going in.

I couldn't figure out why I was shooting terrible points the first 7 stages....like dropping 20pts on a 160pt stage....figured I was trying to go too fast, but it didn't feel that way. This past match, after getting it back on track I think I dropped 3 or 4pts on the first stage (115 total) which is more like what I'm used to.

I'm still keeping my eye out for a deal on an aluminim body C-more just to experiment with. R,

[HoMiE]

Mine used to move, but it doesn't anymore after a little drop of purple loc-tite. I index my screw like you already have figured out. As long as I keep my load the same, hits where it's supposed to.

[jwat]

My friend and I both had similar issues ( losing zero). His ended up being a cracked slide and mine was a cracked c-more.

C-more crack was above windage lock screw all the way to center adjustment plate. Rebody from c-more corrected mine

unfotunately his was a little more expensive.

Jim

[Dave Wilson]

I had the "guess where the dot will be" thing going on at the Steel Challenge this year. On the first day of the match, first stage, I was having trouble hitting steel but I figured it was match jitters. Second stage I was still having problems, but figured I was just trying to push too hard, third stage getting worse, but I chalked it up to nerves, newbie-itus, and still pushing too hard". 4th stage was Outer limits, after a reload while still in the first box.... (yeah , sucked to be me), I went to the second box and, since I was screwed on the run anyway, took my time on the next plate , pulled the r=trigger and watch dust come up WAY to the left. I had to hole 2 inches off of the right side to even hit the plate. I took the gun to the practice range and sighted in, 14" off at 20 yards.

I swapped the c-more out with a spare and never had another problem. I will eventually send the bad one back to the factory.

So , yeah, I feel yer pain!

Dave