Rifle Scopes Will new scope rings and mounts effect my bdc

[dieselgeek]

I just had new rings and dual mounts put on my Remington 700 VTR. The scope I'm using is a Leopold Mark 4 10x40. It has a BDC built into the turrets. So after I zero it at 100 I should be able to click it over to the turrets markings for 200-300 and so on. The new rings are lower than the previous ones I had installed. I've since re-zeroed the rifle at 100 yards, and wonder if I'm going to have any problems with my BDC



Thank s in advance

 

[c ward]

Re: Will new scope rings and mounts effect my bdc

Your BDC is only going to be correct at one set of conditions , the changes in the atmosperic conditions and muzzle velocity will have a much greater affect than the mounts .
Search the site there have been numerous posts about the pro's and con's of BDC's .

 

[dieselgeek]

Re: Will new scope rings and mounts effect my bdc

link? Its hard for me to search via mobile

 

[Jboeri]

Re: Will new scope rings and mounts effect my bdc

recticle bdc isn't based on what the scope is placed in. As long as you have your zero then your bdc should be accurate assuming it was accurate before

 

[ORD]

Re: Will new scope rings and mounts effect my bdc

Jboeri...he isn't talking about a reticle BDC...he's talking about Leupold M3 turrets.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: dieselgeek</div><div class="ubbcode-body">link? Its hard for me to search via mobile </div></div>

Then wait until you have access to a computer (or you can try the link in my sig line below and see if it will operate on your mobile).

The problem in very basic terms with any BDC cam (like your M3 turrets) is that it is designed to work with a specific bullet, at a specific velocity, at a specific altitude/set of atmospheric conditions, etc. If your rifle isn't achieving the same performance with the bullet, and you aren't shooting in a like environment, then the cams won't match up properly. This is the case regardless of the scope mount/base/rings you deploy.

 

[dieselgeek]

Re: Will new scope rings and mounts effect my bdc

As far as ammo goes I've been using 168g HPBT MATCH KINGS

 

[dieselgeek]

Re: Will new scope rings and mounts effect my bdc

Also thank you for answering my question

 

[Pat M]

Re: Will new scope rings and mounts effect my bdc

Yes, it will change slightly ( run ballistic program with different scope heights and see the differences )

 

[ORD]

Re: Will new scope rings and mounts effect my bdc

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: dieselgeek</div><div class="ubbcode-body">As far as ammo goes I've been using 168g HPBT MATCH KINGS </div></div>

You are missing the point on the big picture here. While that may be the correct "bullet" to match your M3 dials...that is only a small part of the total equation. You also need to match the velocity that Leupold calibrated the dials to, etc., etc. You need to chronograph the loads/ammo you are using and determine if you are on in terms of the muzzle velocity you are achieving.

 

[dieselgeek]

Re: Will new scope rings and mounts effect my bdc

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ORD</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: dieselgeek</div><div class="ubbcode-body">As far as ammo goes I've been using 168g HPBT MATCH KINGS </div></div>

You are missing the point on the big picture here. While that may be the correct "bullet" to match your M3 dials...that is only a small part of the total equation. You also need to match the velocity that Leupold calibrated the dials to, etc., etc. You need to chronograph the loads/ammo you are using and determine if you are on in terms of the muzzle velocity you are achieving. </div></div>

No I'm not missing it I understand / understood you 100%

 

[dieselgeek]

Re: Will new scope rings and mounts effect my bdc

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Pat M</div><div class="ubbcode-body">Yes, it will change slightly ( run ballistic program with different scope heights and see the differences ) </div></div>
That's what brought me here.i noticed the change andwondered if it was correct

 

[Badshot308]

Re: Will new scope rings and mounts effect my bdc

Those turrets were calibrated for the M118 load which used the 173 FMJ bullet. The newer loading, the M118LR uses a 175 SMK. A 175 load from Federal or Black Hills will probably be closer to the old M118 load than the 168 SMK loads. In any event, since as ORD stated, your conditions will not likely be the same as what they originally calibrated those turrets under. So zero at 100 and then shoot out to the other ranges and take note of and record the differances.

 

[ORD]

Re: Will new scope rings and mounts effect my bdc

Not all the M3 cams are calibrated for M118/M118LR. They can be had in 168gr SMK for 308, 190gr 300WM, as well as a variety of other factory and "custom" turrets from other manufacturers.

To the OP...whatever cam you have should be clearly marked on the top and should get you started toward figuring out where you need to be.

Good luck!

 

[dieselgeek]

Re: Will new scope rings and mounts effect my bdc

Yeah mine say 168g .308 on them I also have them for.223 and 300wsm

 

[Badshot308]

Re: Will new scope rings and mounts effect my bdc

OK, my M3 was bought back in the early 90's and they came with one marked for M118, one for 30-06, unknown load, one for .300 Win Mag. 220 gr bullet at 2650, and one for .223 rem/5.56, unknown load. My Leupold is so old the box says Made in USA!

 

[dieselgeek]

Re: Will new scope rings and mounts effect my bdc

Ha you mean the box was even made on the usa?

 

[Badshot308]

Re: Will new scope rings and mounts effect my bdc

Yup, the back of the box says Printed in USA.