Rifle Scopes Scope & Base advice please

[ricky5042]

Hi all i have a Howa 1500 in 223 with two piece mounts the front mount is 3.88mm off the reciever and the rear mount is 6.72mm off the reciever and the scope was a Falcon T35 Premier 35x56 and while at east holme we started at 200 yards no problems went back to 300 yards and i couldnt adjust the scope up as it bottomed out with no more adjustment left! looking at the turret i could see just past 4 and when the cap is off to reset the cap to zero it goes upto 6 so i was really surprised the scope wouldnt zero at 300! and when i moved to 400 i had to aim at the top of the frame that holds the target not good! someone sudgested i get a 20 moa single piece mount but i cant find any info on them ie the difference in thickness of the front and back of the mount to see if its much different to what mine already is, i would appreciate some help and input please

Thanks



Rick

 

[UNCIVILIZED]

I can't say that I know Howa's, but is it possible that you do in fact have tapered bases, only they're turned around bass ackwards. That & or you could unknowingly be using rings with built in elevation, & they could be reversed as well. Also, while everything is disassembled, check your scope to see that the reticle's as close to being centered as possible. Some guys use the shoe box with 2 "V" shaped slots in it trick for this.
And this wont fix all of your problems, given that things are so far off right now, but here's a small info bit on tapered bases, & shimming http://snipercountry.com/InReviews/AT_15MinTaperedShims.asp The math therein should be of some help figuring out base tuning.

 

[ricky5042]

Hi thanks for the info i will go and check it out

Rick

 

[okiefired]

That best I can measure my 20 moa base w it on the rifle, I come up w/ .060 difference front to back. You're already at about .112 dif now so I'd say youre problem is elsewhere.

Okie

 

[ricky5042]

That best I can measure my 20 moa base w it on the rifle, I come up w/ .060 difference front to back. You're already at about .112 dif now so I'd say youre problem is elsewhere.

Okie

Hi thats what i was wondering but the guy i got the scope from said he used it on a 308 out to 1000 yards and said i needed a 20 moa base so when i said my rear base is higher than the front he tried to say it may look like it but i probably wasnt so i measured it with a vernier and thats where my figures came from! when i took the cap off to set to zero i noticed that the scope bottomed out at just over 4 on the turret but the turret goes up to 6 so does that meann theres an issue with the scope its self?
Thanks

Rick

 

[okiefired]

Could be a problem. Does the elevation turret adjust all the way DOWN to its marked bottom? As was mentioned earlier, did you check to see if your reticle was centered windage wise?

 

[ricky5042]

Could be a problem. Does the elevation turret adjust all the way DOWN to its marked bottom? As was mentioned earlier, did you check to see if your reticle was centered windage wise?

Hi it winds down to its minimum but not sure about windage so will check that tomorrow and see what it is.
Thanks

Rick

 

[ricky5042]

Hi all iv checked windage and elavation both of which only have 40 minutes from top to bottom and this is from a Falcon T35 and just out of interest iv done the same with the fox 8-32x44 which was on it when i got the gun and it has 60 minutes from top to bottom i also measured the mounts and they are the same, it just seems a bit odd that the guy i got the scope from said he used it from 50 to 1000 with his 308.

Rick

 

[okiefired]

Rick, I still suspect your reticle is way off center when you are zeroed. If it is way off, either in elevation or windage, you can loose a conciderable amount of the travel on your elevation turret. To check, with the scope zeroed, turn your windage turret all the way to stop in both directions while counting either marked moa or clicks. If one is much higher than the other, your reticle is way off center and would limit your travel in elevation. Remember, your erector is moving up and down in a round tube, being off to one side or the other will cause it to hit the tube wall sooner and stop sooner. With 40 moa of total travel and a centered reticle, you would have at least 20 moa of travel UP. With 20 moa of travel and the amount of cant in your base you should be able to easily zero at 300 and well beyond. There are rings and bases available with windage adjustment that can fix this if its the problem. Sometimes swaping the rings front to back or turning one 180 deg. can help. But if you find your reticle is close to center when zeroed, my guess would be a broken scope. If you have access to another scope you know to be good, trying it may save you alot of time and trouble. Good luck and keep us posted.

okie

 

[ricky5042]

Rick, I still suspect your reticle is way off center when you are zeroed. If it is way off, either in elevation or windage, you can loose a conciderable amount of the travel on your elevation turret. To check, with the scope zeroed, turn your windage turret all the way to stop in both directions while counting either marked moa or clicks. If one is much higher than the other, your reticle is way off center and would limit your travel in elevation. Remember, your erector is moving up and down in a round tube, being off to one side or the other will cause it to hit the tube wall sooner and stop sooner. With 40 moa of total travel and a centered reticle, you would have at least 20 moa of travel UP. With 20 moa of travel and the amount of cant in your base you should be able to easily zero at 300 and well beyond. There are rings and bases available with windage adjustment that can fix this if its the problem. Sometimes swaping the rings front to back or turning one 180 deg. can help. But if you find your reticle is close to zero, my guess would be a broken scope. If you have access to another scope you know to be good, trying it may save you alot of time and trouble. Good luck and keep us posted.

okie

Hi okie iv checked the scope and the windage was on the 3 mark on the turret and it bottomed out at just over 4 like the elavation turret and from where it was to complete travel was 14 minutes out of a total of 40 so it does seem to be a bit off, iv wound it up and down a couple of times and set to the centre there is still only 40 minutes from top to bottom of the elavation so im guessing there is an issue with the scope, im going to put the fox scope back on it as i know that was fine out to 400 and il return the scope to the guy i was going to buy it from.
Thanks

Rick

 

[okiefired]

Rick, I'm haveing a little trouble understanding your posts so please excuse me if I'm repeating myself. It sounds like you're saying you're zeroed at the "3" mark and bottomed out at the "4", so you have 1 moa of travel in one direction? That is NOT gonna work. It also sounds like you're trying to "free something up" by winding your elevation turret up and down...thats not gonna work either. Take your set up out to the range and sight it in (zero it) at 100 yrds (or meters or whatever, dosn't mater). AFTER your rifle is hitting where your scope is aimed (zeroed), run your windage turret all the way in one direction. Count the clicks when you do this and write it down. Turn it back that same number of clicks and stop (you're back to your zero). Turn it the oppisite direction and count the clicks and write it down. Calculate the difference in those two numbers and if it is a significant difference (say, 20 clicks if your scope has .25 moa clicks) your scope is way out of alignment with your bore and you will have to take one of the actions I mentioned earlier to correct it.

okie

 

[ricky5042]

Rick, I'm haveing a little trouble understanding your posts so please excuse me if I'm repeating myself. It sounds like you're saying you're zeroed at the "3" mark and bottomed out at the "4", so you have 1 moa of travel in one direction? That is NOT gonna work. It also sounds like you're trying to "free something up" by winding your elevation turret up and down...thats not gonna work either. Take your set up out to the range and sight it in (zero it) at 100 yrds (or meters or whatever, dosn't mater). AFTER your rifle is hitting where your scope is aimed (zeroed), run your windage turret all the way in one direction. Count the clicks when you do this and write it down. Turn it back that same number of clicks and stop (you're back to your zero). Turn it the oppisite direction and count the clicks and write it down. Calculate the difference in those two numbers and if it is a significant difference (say, 20 clicks if your scope has .25 moa clicks) your scope is way out of alignment with your bore and you will have to take one of the actions I mentioned earlier to correct it.

okie

Hi soz il try and start from the begining a guy down my club said he had a Falcon T35 scope 1 1/8th if i wanted to try it, so i fitted it to my howa 1500 in 223 and our range is 50m so i zerod at that range and it wasnt far out. I set it 1 inch high so when we go to the other range it would be close to the 200yard start and i only had to bring it up a few mils and all went well so we moved back to the 300yard mark and went to adjust the scope and it only went up a couple more minutes then it bottomed out which left me 6 inches low so had to aim with the scross hair! we then went back to the 400yard and i had to aim at the top of the target board frame to get rounds on target, the guy who owns the scope was there and he said he shot the scope out to 1000 with his 308 and then said i would need a 20moa base so i said my bases are taller at the back than the front he said it only looks that way which is why i measured the bases to see what the difference was and it was as stated in previous post, i set it back to the 50m setting and it goes up 8moa and down 32moa so im guessing there is an issue with the scope its self rather than my rifle ammo setup.
Thanks

Rick

 

[okiefired]

Yes, I understood that, everything I've said still aplies. If your base had too much cant (high in the back, low in the front) you would be unable to zero it at shorter distances, not longer. Sooo, you have yet to make sure your reticle is centered in the tube when you're zeroed ( sighted in )? Untill you do this, you cant eliminate misalighnment caused by the rings or base.

okie

 

[ricky5042]

Yes, I understood that, everything I've said still aplies. If your base had too much cant (high in the back, low in the front) you would be unable to zero it at shorter distances, not longer. Sooo, you have yet to make sure your reticle is centered in the tube when you're zeroed ( sighted in )? Untill you do this, you cant eliminate misalighnment caused by the rings or base.

okie

Hi no trouble with close range zero so i will re zero at our 50m range and see what the windage gives me.
Thanks

Rick