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Discussion Starter #1
So I have been trying to help a friend of mine get his CVA Optima 45 cal sighted in. We first started with a very old cheap scope and I told him that it had to go so he ordered a new 3x9x40 Thompson Center scope like I have on my CVA. We mounted the scope today and off to the range to what I thought would be a short trip. Two hours and 40 rounds later we still do not have this gun shot in. I performed field cleaning every 10 or 12 rounds. We were shooting at 25 yards and we just couldn't get this thing zeroed. I like to feel that I am pretty good at this stuff but right now I am at a loss. I am looking at several things like, human error in markmanship, fouling of the barrel, a brand new scope that is bad, or a bad gun. Is it possible that this gun only likes shooting 1 or 2 rounds before it needs cleaned? Any tips or suggestions would be appreaciated.
 

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When zero'ing mine I clean between every shot. just a patch on a jag with a good cleaning solvent and several dry patches. However, I read that you changed scopes to a more durable scope but I would also change the mounts, that is probably your problem. just my 2 peso's.
 

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We discussed changing the mounts but to be honest with you I can't see how they could be the issue. He bought the gun off of somebody we know who bought the gun brand new and shot it very few times. The mounts came with the gun when he bought it. It is definately something to consider though. Thanks for your input.
 

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cheap scope mounts will always be a headache.

TC scopes lately ive been reading on are junk these days. Some are getting around 20 shots before they start throwing shots all over the place.

Try open sights and see.

You didnt say what load youre shooting or what youre doing in between shots.
 

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What have you been doing with powder charges? Sometimes guns get finicky about how much powder is used and will throw shots all over the place.

I would start by using a minimum powder charge, 50 - 60 grains and see if you can get that to group and then move up. If the powder charge doesn't work then try frontier gander's suggestion with the open sights, if that doesn't work you may need to experiment with the bullet you are using. the CVA manual will have recommendations for powder charges.
 

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What kind of powder? How Much? Trip 7 has the infamous crud ring.

For sighting in swab between every shot, wet patch then dry patch.

Keep everything as consistent as possible from shot to shot. Measure the powder the same each time, pour it down the barrel the same each time, when loading the bullet, load it and seat it on the powder the same each time. Even down to the same pressure on the rod each time.

What kind of projectiles are you using. Could they be undersize?

There are a number of things that could be wrong.
 

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Discussion Starter #7
He is using the same loads that I use in my CVA. I bought mine several years ago and was pointed in the direction of using TC Super 45XR 180gr. XTP Mags. with two 50 grain Hodgdon Pyrodex Pellets (100 grains). This set up is dead on deadly accurate with my CVA which by the way has a 3x9x40 TC scope on it. So we set his gun up the same way and these are the difficulties that we are facing. One note though, he did some reading on the scope last night and read 2 interesting things. The scopes adjustments are 1/16" for every click at 25 yards and it states that you should fire 3 rounds through the gun before making anymore adjustments. I have been taught to tap on the scope after making adjustments so I would think that would mimmick the 3 shots. We are going to look the gun over carefully tonight and then go back to the range and start over. Thanks for everybody's input.
 

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FYI, the 1/16" @ 25 yards is equal to 1/4" @ 100 yards(So, it's completely normal and typical for a scope....most are 1/4 MOA at 100....some are 1/2 MOA at 100....target scopes are often 1/8 MOA at 100).

1/16" @ 25 yards
1/8" @ 50 yards
3/16" @ 75 yards
1/4" @ 100 yards
....and so on.


In reality, it's not even inches, but minute-of-angle. Inches is close enough for most....especially with a muzzleloader. One MOA=1.047" @ 100 yards.
 

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First thing I would do is to scrub the bore, and make sure it does not have plastic, copper, or lead fouling. Get it back to raw steel. Use a bore brush with a good solvent, swab with dry patches, and then coat the bore with the bore solvent (Hoppes #9 benchrest works well) and let it set wet overnight. Next day run dry patches thru the bore. You may have to do this for several nights, depending on how clean your dry patches come out. Next, scrap the pellets, and use granular powder. Try using Pyrodex RS, and start with 60, to 70 grains, and work up in 5 grain increments. Swab between shots. Make sure the barrel does not heat up too much, let it cool. I also would use a 240, or 250 grain bullet/sabot combo. If you get good results with these projectiles, then try the 180's. Every gun shoots differently, even the same models. Just because yours likes a certain load, another may not. Good luck.
 

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i install a lot of scopes for other hunters and shooters.

The gun is first boresighted at home using a laser boresighter. The distance is 25 feet. The boresighter comes with attachements for various calibers; it fits in the muzzle of the gun. These cost as little as $30: It can save you a lot of time, money and frustration at the range.

At the range the target is put at the 50 yard line. My target frame has a backer board that measures 24" wide by 24" high. The target is usually a two inch bullseye. The first round is almost always on the backer. If the shot is not on the backer, the target comes back to the 25 yard line for scope adjustment.

i fire two rounds before making scope adjustments. My scope adjustments are bold. Once the rifle is sighted in, i fire a three shot group to confirm the zero.

If you are using Pyrodex or 777 it's usually necessary to swab the barrel with a damp patch after every shot, followed by a dry patch or two.
 

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What twist is in the Barrel? It may not be suitable to stabalize 180 ggrain bullet . Try 250 grain and 3oo grain with 100 grain load and see what group you get. I tried 180 grain an could get it to stabalize and went to 300 grain bulleu and got 1 in group at 100 yards, be sure to spit patch between shots. Dont be afraid of trying 3 shot groups with different primers. You might get a suprise. good Luck
 
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