Long Range Hunting Online Magazine

Go Back   Long Range Hunting Online Magazine > Hunting > Long Range Hunting & Shooting

Long Range Hunting & Shooting Nightforce Optics


20 MOA RAIL & JBM Question

LinkBack Thread Tools Display Modes
Unread 08-28-2013, 10:21 PM
Gold Member
Join Date: Aug 2007
Location: Canterbury, New Zealand
Posts: 675
Re: 20 MOA RAIL & JBM Question

Do you need a 300 yd zero with the 300 wsm for it to work?
Reply With Quote

Unread 08-28-2013, 10:55 PM
Platinum Member
Join Date: Dec 2009
Location: LaPine Or.
Posts: 2,541
Re: 20 MOA RAIL & JBM Question

Originally Posted by kiwi3006 View Post
Do you need a 300 yd zero with the 300 wsm for it to work?
No no no,
I just used my 300yd pin & zeroed it at 300 so I could salvage a bear hunt last week.
Smoked my bear at 423yds. Holding between my 300, & 400 yd pins, so it worked, but NOT how I wanted.

I zeroed it at 200 slingin 180's at 3085 fps with my 300Wby, & it shot Great out to 600.
So, I figured 180's at 3100+ out of my 300WSM would be quite similar. Something is not right. Even JBM says it should be right there with Leupolds Sub Tensions.
I'm confused.
"Its not Rocket Surgery.....'

"I have No idea why that cop made me ride in the back seat, when I Clearly called Shotgun!"
Reply With Quote
Unread 08-30-2013, 08:50 AM
Official LRH Sponsor
Join Date: Jun 2004
Location: Fort Shaw, Montana
Posts: 6,848
Re: 20 MOA RAIL & JBM Question

For what it sounds like your using this rifle for, hold over shooting will be perfectly fine. I admit that dialing up is more precise but if your drops are figured accurately and your not shooting much over 800 yards, hold over will be faster in the field and no chance of loosing your zero in the field either.

I have been holding over for a long time and have taken over 30 head of big game from ranges between 500 and 950 yards with all but two taken with one shot. Those two were pilot error on the first shot which were clean misses and after correcting my mistake, the second shot were both clean kills.

THe problem with hold over shooting at ranges past 800 yards is that most scopes have some parallax in the field of view and when your using a reference mark that is farther down on the vertical stadia of the reticle, you get some of that distortion and consistency suffers.

For sub 1/2 mile shooting I hold over, for past I dial up. I am not saying hold over shooting is as precise as dialing up, even at moderate ranges such as 400-600 yards but its MORE THEN accurate enough to put the first shot into the vitals of a big game animal with a lot of room to spare. All comes down to getting your drops figured accurately and testing them.

With a properly set up system, its easy to put first shot within 1/4 moa of point of aim using hold over. Now if your shooting groups, I am sure your groups would be bigger using hold over because at times you are estimating between reference points but for killing big game, it work perfectly well.

Both systems have advantages and disadvantages. For under 800 yards, in my opinion, hold over is better for big game hunting, for over 800 yards dial up is better.

Back to your problem, I am sure it is something simple. One thing I would do it reverse engineer your drops to see whats going on. By that I mean, for example, find what your bottom reference line is supposed to be impacting at and set a target up at that range, for example, say its 750 yards. Set a target up at that range and then basically zero your rifle with that reference line at that target distance.

That way you know your rifle will hit on point of aim at that range using that reference point. Then work your way back and record your results. Make sure your scope is set up on the correct power. In fact from what you describe, I would say there is something off with the power setting on your scope.

I like setting a scope up this way because it removes some of the error we see when we zero at closer ranges and then shoot at longer ranges. Just helps speed up the drop chart development. If you are zeroed at long range the error at closer range will be less and also less significant whereas a small error in sight in at close range will result in a much larger error as range increases.

Now to your scope. The Varmint reticle is not the best for hold over shooting much past 500 yards. There is a lot of room between each reference point and they are inconsistent in spacing. A MUCH better reticle for hold over shooting is the TMR reticle and that may be something you want to look into.

Second focal plane reticles are also not the best for long range hunting with hold over shooting because your locked into one power setting, usually the top power setting and in many cases that not the best one for big game hunting. A First Focal Plane scope is far better as reticle stays consistant with target at all power settings.

NO problem using a SFP scope for hold over shooting, just not as flexible.

Hold over or dial up makes no real difference, for big game hunting out to 1/2 mile or so, it comes down to what you want to use and what you are comfortable using. Both systems will get the job done perfectly well, both have advantages, both have disadvantages. Pick a system and practice a lot and you will be just fine.
Kirby Allen(50)

Allen Precision Shooting
Home of the Allen Magnum, Allen Xpress and Allen Tactical Wildcats and the Painkiller Muzzle brakes.

Farther, Faster and Flatter then ever before.

Web Page: www.apsrifles.com

Reply With Quote
Unread 09-12-2013, 10:56 PM
Junior Member
Join Date: Sep 2012
Posts: 29
Re: 20 MOA RAIL & JBM Question

Have you had any luck settling this?
Reply With Quote


Thread Tools
Display Modes

All times are GMT -5. The time now is 12:35 AM.

All content ©2010-2015 Long Range Hunting, LLC