HELP!!! Why cant i keep a scope on my axiom??

[Pasidewinder]

Ok fellas, I need some help. I bought a axiom smf last fall, when i took i out of the box it shot excellent, one hole groups. As season went on i would check zero now and again as i adjusted brace height ect. I noticed the groups getting more and more irradic each time i shot. I use sand bags and have even used my machined rifle rest to elliminate any human error.

By the end of season the best i could do was about 6 inches all around the bull in any direction but mostly left and right. I tried a swift shotgun scope on it after season and the same thing happened, at first it shot great then after a while it too would not hold a group. I gave up on it for a couple months until today, i had a nikon rimfire scope laying around and decided to try it out temporarily until my origional gets back from danny miller. Same story, the bow shot great for 20-30 shots then at 25 yds it started shooting about 6-8 inches high from zero and slightly left-right at times. I have checked, rechecked and tripple checked every fastener on and in the bow and ALL are tight. I shoot the stock firebolts with 125 grn tips, and have even tried my 125 grn slick trick magnums and the results are the same, on every scope ive had to almost bottom out the elevation screw to get the bow to not shoot high. I know i can remedie this with a hair taller set of rings, but heres another problem, im haveing a hard time finding a set of rings that will secure to the weaver style rail, i put them on and attempt to tighten them down but once tight i can still rattle the rings and move them with my fingers! Its like the rail is on the narrow side. I come from an extensive background with fire arms and installing scopes so i know the ins and outs of it but this has me puzzled.

Any help would be appreciated, I have lost all confidence in this bow, ive even considdered selling it, but the loss on my end would be too great right now to put enough to it to get something else. Sorry for the long post, but i just wanted to put all info out there and see if anyone has any advice, thanks in advance.

[canoe13]

Are you using the same rings with each scope? Perhaps the rings are defective. Do they fit other scope rails tightly? I have a Tact-zone scope with factory rings that won't mount tight to my Matrix 355 and I know that it is the rings at fault because other rings mount just fine on the bow. I plan on contacting CS to get a new set. I am sure Excal. will replace which ever part is defective the scope base or the rings. once you figure out the problem.

[Hunt it]

Check all scope base screws where attached to bow. If they are all tight then you need a quality scope.

[chuckinator]

Sounds like a puzzle. Seems you've tried it all. Try shooting your bow without a scope sort of iron sites. I had the scope on my Grizzly break so I shot using the visual site of the tip of bolt for windage and sited down the weaver style scope rail on the bow for elevation. Started at 10 yards because it was a trial and error how low to site thru the rail so I could hit the bag.consistantly in the same spot. Once you figure your siting you can see how the bow groups and eliminate it as a contributing factor for the problem you're experiencing. Then for sure it's the scope rail.

[chuckinator]

Oh yea, the scope rings supplied by Excal are pretty cheap China made ones. As stated by another member, try different rings. I used lock tite on my screws which helps. The large screws on my excal rings came loose after 20 or so shots. That's when I used lock tite. Been ok for now. Going to by good steel rings like on my rifles.

[Deerstalker]

You have 6 screws that hold the scope mount rail & trigger housing. Two under the stock which MUST be removed to get to these 2. Four screws through the rail into the top of the trigger housing. Then you have all of the scope ring screws. Make absolutely sure that ALL of these screws are tight and that there is NO movement between the trigger housing and the shooting rail. I do NOT shoot the same bulls eyes more than once because of arrow damage and your Axiom SMF should/must be the same way. I believe that you will find one or more of these screws somewhat loose. Keep us posted please.

Firebolts in this target.


Weaver tactical rings medium on Nikon Bolt Xr.

[L. E. Carroll]

Do you live state-side or up North... if state-side ? I just today took the stock scope base off of my new Axiom to put the new ADF style one on that came in today via UPS from Danny Miller.... The stock ones yours if you need it... just pay shipping.

Hopefully, you'll be able to narrow it down even more, as that way you can eliminate the possibility of a too narrow scope base..... I know the one I'm offering is ok.

Gene

[Pasidewinder]

Thank for the ideas fellas, but i have checked ALL fasteners several times outside and inside. I took the stock off and checked all of these as well, this bow is tight and solid.

Even the stock excal rings wouldnt tighten onto the rail, the set that is on it now are very tight and secure. Im thinking that i have just had a run of bad scopes, i know these bows can be hard on lower end scopes, the scopes that i have tried except the origional ( i dont know much about excals scopes) have been pretty decent made scopes from mfgs that have held up well for me in the past.

Im sending the origional back to danny miller, but hopefully i can get ahold of something that will hold up for me.

[flightattendant100]

X2 on checking all the bolts including the two that hold trigger unit to rail. Also suspect a better set of rings would help you. The Leupold Rifleman rings are a quality ring at a bargain price. If the above doesn't fix it, then a quality scope may be your route. You will not regret having a better quality optic. I am partial to the Leupold scopes and Danny Miller may give you credit from your Excal scope toward one. Worth asking about. Danny also has an upgrade ring I think. Ask about those as well.

[xcaliber]

That sounds very odd indeed. Make sure the rings are the right size for the scope, then tighten them to the scope off the rail, make sure they will tighten until no movement at all is noticed. Now, take the scope out of the rings, open the base clamps up as far as you can without loosing parts! Make sure the base is in the grooves on the rail, front, and back, then snug them up a little in the front, a little in the back until both ends are snugged. Again, make sure no movement in the rings, if so, make sure it is not the scope mount on the crossbow, they do come loose!!! I recommend carefully taking out the fasteners, and putting a drop of Blue, 242 Locktite on them, careful not to over do it, and do not get that stuff on the stock, or any plastic, let cure 24 hours minimum before shooting. You should hit nickles all day at 20 yards unless your arrows are bunk!

Good luck.

[Pasidewinder]

L.E. Carroll, thank you very much for your generous offer, i believe im going to maybe try a better quality scope first before i change anything, i believe 100% that the rings i have on the bow right now are tight and secure.

But i will take you up on your offer in the case that a better quality scope doesnt solve my problems. I was looking at the luopold shotgun scopes for my slug gun, im going to try to pick one up and try it on my crossbow as i have heard good things about them for this application, and then atleast im not out nothing because i can still put it on my slug gun also if it doesnt solve my crossbow problem.

Once again thanks for the offer sir.

[foofoo]

i have had scope ring issues tightening to the scope base. mostly on the older style rails and using low rings especially the steel Warne rings.seems the tolerences are out of wack between weaver and picatinny and the older Excal rails were an issue for me. no matter how tight you could still push the rings back and forth. i would have them put a new style scope rail on or maybe upgrade to a anti dry fire unit.

[miller1buc]

Unless I am reading it wrong it sounds like you identified the problem of not having a set of rings that will tighten down. I just experienced the same thing when I replaced the stock scope on my Micro. I bought a higher set of rings since my new scope needed more clearance. I tightened then down to mount the scope and all seemed tight. After 3-4 shots I heard a rattle and noticed there wasn't a consistent pattern. I checked and all screws on the rings were tight but I could wiggle the scope back and forth on the base. I bought a set of Leupold rings that had a deeper lip on the part that connects to the base mount and all was solved.

[Deerstalker]

One other thing to check and this may not be the way your rings are made BUT I believe that on some rings you can rotate the small clamping bar 180 degrees and it my look right but it will fail to tighten up properly to the weaver style rail.

[L. E. Carroll]

Pasidewinder ....I sent you a PM.

Gene