Hunting w/Maximum Point Blank Range (MPBR) vs BDC scopes

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mntnflyr4fun

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2nd focal plane (SFP) BDC scopes,with a “busy” sight picture for extended range shooting (300yds+) seems counter-intuitive to the idea of increasing accuracy at distance and quickly getting cross hairs on target and a bullet down range. If not a busy sight picture, you have your mind on twisting knobs counting clicks or looking at tiny engraved markings on your elevation knob hoping to get the scope set before the game disappears behind some brush across the canyon before you are ready to get back to the job of shooting.

Throw in low light, the reduced eyesight that comes with aging eyeballs on top of the adrenaline rush of finding a browsing bull 500yds across a canyon and it’s a disaster waiting to happen..

I sold my last BDC scope and bought another Zeiss Conquest with a std. Z-plex and began looking into other methods of gaining long range accuracy without doing the old “hold over and hope” type of shooting that comes with a conventional sight-in practice of setting up for a fixed 200 or 300 yard zero or grandpa’s “1 ½” high at a hunerd” is all you’ll ever need idea.

Using the Sierra Infinity program (others can get you to the same place, I am just used to using InfinityV6) I locked onto the concept of using the MPBR (Maximum Point Blank Range) calculation to define my sight in range to provide a minimum of two fast acquisition sight points with a 3rd to extend the range if need be. The idea being a maximum range that the bullet will remain inside a defined kill zone size. Fast and accurate was what I wanted and the MPBR method seems to fit like a glove.

Using this method a defined kill zone size is designated based on the size of the game you are planning to hunt. In my case, I was building a 30-06 load for elk hunting out to 500yds and I chose a kill zone size of 15” for Roosevelt Elk in the Oregon Coast Range.

Running the MPBR calculation resulted in a MPBR of 399yds for my load of a 200gr. Nosler Accubond at 2688fps, 24” bbl.

To achieve this I sight my gun in for a 337yd. zero which equates to sighting in 5.6” high at 100yds.

The result is that I can hold dead on (center mass) from 0 – 399 yds and hit inside the 15” dia. kill zone. No hold over etc., if the rangefinder says ts under 400yds., center up and send the bullet downrange and it will not be higher or lower than 7.5” from where I have the crosshairs. Dead Elk.

There is a 2nd easy to find/acquire hold point to extend the MPBR approach, and that is the top of the back (TOB). In my case, I assumed the TOB to bottom of chest at 30” so with my aim point out to 400yds being pretty much center mass, there is an additional 7.5” to the top of the back.

Referencing once again the data generated during the MPBR calculation and following the bullet path to the range where the bullet has dropped to -23.5” (15” kill zone +7.5” more to the TOB) gives an extended range of 487 yards. Being able to quickly make the decision of the range being over 400, but under 488yds with my rangefinder, I can quickly decide on a center mass or TOB hold and know that I can put a round in the kill zone if I can do my part.

Lastly, a simple tweak to extend the range even further with very limited “Kentucky windage”.

At the extreme limits of the ranges discussed above will produce hits at the bottom of the 15” kill zone. So in fact if the range exceeds the 2nd range point of 487yds where your bullet will hit at the bottom of the kill zone, you really still have a 3rd hold over point that is up to 15” above the back to still put one in the top of the kill zone.

In my case, this range turns out to be (23.5”+15”=38.5” total drop) puts my extreme range right at 550yds. Only now the bullet will be entering the kill zone at the top of the 15” circle instead of the bottom….

I feel this gives me a credible 3 point 550yd ranging system that is quicker than a massive range table taped to my stock, or a difficult to see jumble of lines/dots/knob markings etc. where I can easily make a selection mistake or take to long to setup. I expect to be able to reduce my kill zone size during load development as a true 500yds is as long as I plan to shoot, but 15" is a good starting point for now.

This same method can be easily used for any game you choose to target with the same load. It is a simple matter of running the MPBR calculation on a larger or smaller kill zone, following the range data to come up with a TOB hold and a max holdover point based on drop, making the zero range adjustment to the scope and head off to chase moose, deer or antelope etc.

With the money saved on an expensive BDC scope you can buy a top of the line standard scope setup with Duplex reticle to make it a slam dunk to see where your crosshairs are.

My last observation would be that this technique would work even better with a first focal plane (FFP) scope as the crosshairs would grow in size along with the target at higher magnifications opening up more possibilities to get the crosshairs right on the money. Alas, FFP scopes seem for some reason to be made of gold dust or something as I have yet to run across a comparable scope to my Leupold VX3 or Zeiss Conquest with the FFP arrangement that I can afford.

Anybody that can poke holes in this I am listening…….
 

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I’m not qualified to poke holes in your method but I don’t see anything drastically crazy.

I am a MPBR kind of shooter too and I appreciate the simplicity of just placing the crosshairs on the target and shooting. I accept the limitations associated with this and am happy with the results.

I sort of feel bad for the folks out west who have wide open spaces and are faced with the decisions to extend the range of their rifles in a better attempt to be able to shoot it if they can see it.

I feel blessed to be able to use a 444 Marlin with 300 gr bullets as my long range rifle.

You seem to have found a system that works for you and there are many ways to skin this cat.
 
I am a believer in MPBR, but much of that bias comes from spending most of my life shooting open sights on muzzleloaders. I am further biased toward closer shots - I might hit the dirt at 400 yards, but I am not going to take game at that distance with a traditional front-stuffer.

Living here in New Mexico, there are some long stretches of open country. Given that, I have trouble pushing back on how I have been educated as a hunter (and, I admittedly hunt more than I kill), which is to get in range. Getting in range means putting the sneak on and getting close to the critter, and not taking shooter shots - getting close and taking hunter's shots.

My logic is that if a bow hunter can get close enough to take an antelope or elk out here, then I probably should be able to get within rifle range with some effort. It has been confirmed by long shots that didn't result in clean kills, and closer shots that were clean misses for whatever reason.

I am somewhat curious about your plans to hunt the Coast Range and be prepared for 500 yard hunts. Having lived a significant part of my life in Oregon, my hunting experience in the Coast Range and the wet side of the Cascades is that long shots can be taken, but don't need to be (the much discussed shooter's shots versus hunter's shots). But I do stand with the concept of MPBR shooting, as it both can save significant $$$ on glass, and most shooters aren't good enough to make 500 yard shots on game. Like I said, my bias is based on the (maybe negative) influence of my ML shooting for all these years, and the fact that I've met a lot of bow hunters that can get close which leads me to thinking I likely should be able to as well. Plus, tracking a critter that has been wounded from 400 yards can take up a big part of your day...
 
I am a believer in MPBR, but much of that bias comes from spending most of my life shooting open sights on muzzleloaders. I am further biased toward closer shots - I might hit the dirt at 400 yards, but I am not going to take game at that distance with a traditional front-stuffer.

Living here in New Mexico, there are some long stretches of open country. Given that, I have trouble pushing back on how I have been educated as a hunter (and, I admittedly hunt more than I kill), which is to get in range. Getting in range means putting the sneak on and getting close to the critter, and not taking shooter shots - getting close and taking hunter's shots.

My logic is that if a bow hunter can get close enough to take an antelope or elk out here, then I probably should be able to get within rifle range with some effort. It has been confirmed by long shots that didn't result in clean kills, and closer shots that were clean misses for whatever reason.

I am somewhat curious about your plans to hunt the Coast Range and be prepared for 500 yard hunts. Having lived a significant part of my life in Oregon, my hunting experience in the Coast Range and the wet side of the Cascades is that long shots can be taken, but don't need to be (the much discussed shooter's shots versus hunter's shots). But I do stand with the concept of MPBR shooting, as it both can save significant $$$ on glass, and most shooters aren't good enough to make 500 yard shots on game. Like I said, my bias is based on the (maybe negative) influence of my ML shooting for all these years, and the fact that I've met a lot of bow hunters that can get close which leads me to thinking I likely should be able to as well. Plus, tracking a critter that has been wounded from 400 yards can take up a big part of your day...

I hunt exclusively in an area that has been and is still continuously logged which means many roads in large drainages overlooking canyons where I spot elk at up to a mile or more away, then endeavor to get as close as possible for the shot. I have been hunting the same area for 40 years and in the last 15 years due mostly to increased hunting pressure via more seasons/tags/people, the elk in the area I hunt are getting much more reclusive and stay further away, creating much longer shots and the steep/rainforest/logging slash covered ground does not remotely lend itself to getting closer although you are welcome to come out and try to take a 500yd walk where I hunt, 40 degree slopes are pretty darn common ground. When I started in this area 40 years ago, we successfully harvested all our game in 200 - 250 yd shots. Almost impossible to do that today, as the bulls remain in dense cover much further out. My last 5 bulls averaged between 375 and 425 with one being taken at 525 and in my lifetime (15+ bulls) only 1 was taken under 200yds and all animals dropped where they stood as I am also not interested in tracking wounded game in this terrain. I can shoot the distance and hit where I need to refined by a lifetime of cross canyon shooting and I use heavy for caliber, premium quality bullets designed for the task at hand, so this isn't a matter of me wanting to take unethical long range shots, but tuning my tools to the job at hand. Unfortunately, "Getting close and taking hunter's shots" just isn't practical in your context and to assume differently is at best poor judgment on your part and for that matter your criticism applies as well to muzzle loading, the ranges are just a bit different. Thanks for the feedback tho, although I was kinda looking for some context on the process I proposed vs other long range shooting strategies for those of us not able to walk up and touch our game from 75yds away..
 
Knowledge is knowing a tomato is a fruit wisdom is not putting tomatoes in a fruit salad.
My problem with MPBR is way too many hunters just plug the numbers into a ballistics calculator and then go out and zero the gun X" high at a 100 and think ooh I'm good to 400. Problem is they shoot 3 shot groups of 1.5 to 2 moa and didn't account for a cross wind when they sighted in. So now they're really only 1/2" high at 100 and 1/2" left. On top of that they used the advertised velocity from a 26" barrel and their gun is 22 and their velocity is 150 fps slow.
MPBR is fine as long as you know YOUR actual velocity and have gun zeroed at the correct yardage. I'd prefer you actually shoot at your MPBR and verify drop.
As to a SFP ranging reticle why do you think I can't dial 1 mil up from my 100 yard zero (using my 308 AR for reference) and set my scope at 3 or 4X for any shot out to 300 if I need to shoot further I can zoom to 9X as easily as you and then choose weather I dial more or just use the mil marks which incidentally the next 4 are close enough to 50 yard increments for sure.
As for FFP scopes I don't like them the reticle is never the right size. If it's fine enough to be useful at high power for long shots it's very fine and hard to see at low power for fast close shots. If you make it wide enough to be good at low power close then it'll cover too much target at high magnification at long range.
 
Knowledge is knowing a tomato is a fruit wisdom is not putting tomatoes in a fruit salad.
My problem with MPBR is way too many hunters just plug the numbers into a ballistics calculator and then go out and zero the gun X" high at a 100 and think ooh I'm good to 400. Problem is they shoot 3 shot groups of 1.5 to 2 moa and didn't account for a cross wind when they sighted in. So now they're really only 1/2" high at 100 and 1/2" left. On top of that they used the advertised velocity from a 26" barrel and their gun is 22 and their velocity is 150 fps slow.
MPBR is fine as long as you know YOUR actual velocity and have gun zeroed at the correct yardage. I'd prefer you actually shoot at your MPBR and verify drop.
As to a SFP ranging reticle why do you think I can't dial 1 mil up from my 100 yard zero (using my 308 AR for reference) and set my scope at 3 or 4X for any shot out to 300 if I need to shoot further I can zoom to 9X as easily as you and then choose weather I dial more or just use the mil marks which incidentally the next 4 are close enough to 50 yard increments for sure.
As for FFP scopes I don't like them the reticle is never the right size. If it's fine enough to be useful at high power for long shots it's very fine and hard to see at low power for fast close shots. If you make it wide enough to be good at low power close then it'll cover too much target at high magnification at long range.

I hear you, I reload, will be chronographing my loads and have access to a 300yd range to see whats really going on. I use the theory to validate concepts, but always prove em before hunting season as even as a resident, I generally have $1k in an elk hunt so don't risk that with unproven ideas. My comments re:FFP/SFP were related to poor light/old eyes and the fact that SFP reticles remain one size vs FFP where the reticle grows as you increase magnification. Surely was not saying SFP doesn't work (my Zeiss Conquest with Z600 worked fine), I just couldn't see the crosshairs well right at dusk/sunrise looking into a dark timber background hundreds of yards away. For me, being able to dial up the magnification and have the crosshairs get a bit bigger would help me get on target.
 
Using this method a defined kill zone size is designated based on the size of the game you are planning to hunt. In my case, I was building a 30-06 load for elk hunting out to 500yds and I chose a kill zone size of 15” for Roosevelt Elk in the Oregon Coast Range.

I used to mpbr. The issues I see are accuracy of your individual rifle, wind deflection, and kill zones. Most kill zones are based on average animal size. The particular one you are shooting can and will vary in kill zone size. As far as accuracy a 2 moa rifle doubles, or could double the drop in inches you state that's 10 inches at 500 yds. Your assumption is that each shot is point of aim. Then you have to factor wind, speed direction weather it gusts or changes direction down range.
 
Had another quick thought. To take more variables out you need to chronograph your loads in the conditions that you hunt. Elevation, atmospheric pressure, and temp all effect velocity and trajectory of a given load. So shooting in the heat of summer then hunting at 500 yds in sub zero temps may make your shot hit dirt at 450.
 
Had another quick thought. To take more variables out you need to chronograph your loads in the conditions that you hunt. Elevation, atmospheric pressure, and temp all effect velocity and trajectory of a given load. So shooting in the heat of summer then hunting at 500 yds in sub zero temps may make your shot hit dirt at 450.
I appreciate your feedback, all those are valid points, but all those variables exist with a drop compensating scope, open sights or any other sighting devices etc. I get all risks associated with thinking this way, my total focus has been to come up with a theoretical plan, validated by shooting. Two issues that I have had to contend with when using SFP BDC scope (ie Zeiss Z-600) is that FOR ME the scope is hard to see and to work properly has be be set at a pre-determined magnification. I am after a way to choose my magnification and then not be distracted by the clutter (my perception) of lines/dots/circles etc. I live at 300ft elevation, and hunt at 1000 +/- so big elevation changes etc. don't come into play much. I am building hunting loads so am not using precision dies etc., but pay attention to my handloads and am interested to see if this quick ranging method can simplify the times when the range gets out there a bit. You say you "used to mbrp" what are you now doing in place of that?
 
To be honest I don't generally like BDC reticles for most purposes. I've got a couple guns with louping trajectory that are ok IE I have a Leupold VX hog on a 450 bushmaster.
Here's a image from my streloc app Screenshot_20200105-151338.png
For anything that sees extended ranges I prefer a simple mil based reticle.
Here is my 308 set with 1 mil elevation both have target at 200y Screenshot_20200105-151621.png
 
am building hunting loads so am not using precision dies etc., but pay attention to my handloads and am interested to see if this quick ranging method can simplify the times when the range gets out there a bit.

I load for hunting as well. Most of my loads are sub moa, not all mind you but most.

I zero at 200 and unless, I'm sitting in a hedge row overlooking a corn fields where 500 is possible, most of my hunting is in heavy woods and shot distance is limited to 100 or less.

Of the different bdc recticals I use I like the circles the least, because the sun points are less offer the least precision.
 
Makes sense.. but I like the idea of of ranging, and setting my dial for the desired yardage on my CDS Leupold and being dead on out to.. however far..

If it works.. I'll know in a few weeks.
 
2nd focal plane (SFP) BDC scopes,with a “busy” sight picture for extended range shooting (300yds+) seems counter-intuitive to the idea of increasing accuracy at distance and quickly getting cross hairs on target and a bullet down range. If not a busy sight picture, you have your mind on twisting knobs counting clicks or looking at tiny engraved markings on your elevation knob hoping to get the scope set before the game disappears behind some brush across the canyon before you are ready to get back to the job of shooting.

Throw in low light, the reduced eyesight that comes with aging eyeballs on top of the adrenaline rush of finding a browsing bull 500yds across a canyon and it’s a disaster waiting to happen..

I sold my last BDC scope and bought another Zeiss Conquest with a std. Z-plex and began looking into other methods of gaining long range accuracy without doing the old “hold over and hope” type of shooting that comes with a conventional sight-in practice of setting up for a fixed 200 or 300 yard zero or grandpa’s “1 ½” high at a hunerd” is all you’ll ever need idea.

Using the Sierra Infinity program (others can get you to the same place, I am just used to using InfinityV6) I locked onto the concept of using the MPBR (Maximum Point Blank Range) calculation to define my sight in range to provide a minimum of two fast acquisition sight points with a 3rd to extend the range if need be. The idea being a maximum range that the bullet will remain inside a defined kill zone size. Fast and accurate was what I wanted and the MPBR method seems to fit like a glove.

Using this method a defined kill zone size is designated based on the size of the game you are planning to hunt. In my case, I was building a 30-06 load for elk hunting out to 500yds and I chose a kill zone size of 15” for Roosevelt Elk in the Oregon Coast Range.

Running the MPBR calculation resulted in a MPBR of 399yds for my load of a 200gr. Nosler Accubond at 2688fps, 24” bbl.

To achieve this I sight my gun in for a 337yd. zero which equates to sighting in 5.6” high at 100yds.

The result is that I can hold dead on (center mass) from 0 – 399 yds and hit inside the 15” dia. kill zone. No hold over etc., if the rangefinder says ts under 400yds., center up and send the bullet downrange and it will not be higher or lower than 7.5” from where I have the crosshairs. Dead Elk.

There is a 2nd easy to find/acquire hold point to extend the MPBR approach, and that is the top of the back (TOB). In my case, I assumed the TOB to bottom of chest at 30” so with my aim point out to 400yds being pretty much center mass, there is an additional 7.5” to the top of the back.

Referencing once again the data generated during the MPBR calculation and following the bullet path to the range where the bullet has dropped to -23.5” (15” kill zone +7.5” more to the TOB) gives an extended range of 487 yards. Being able to quickly make the decision of the range being over 400, but under 488yds with my rangefinder, I can quickly decide on a center mass or TOB hold and know that I can put a round in the kill zone if I can do my part.

Lastly, a simple tweak to extend the range even further with very limited “Kentucky windage”.

At the extreme limits of the ranges discussed above will produce hits at the bottom of the 15” kill zone. So in fact if the range exceeds the 2nd range point of 487yds where your bullet will hit at the bottom of the kill zone, you really still have a 3rd hold over point that is up to 15” above the back to still put one in the top of the kill zone.

In my case, this range turns out to be (23.5”+15”=38.5” total drop) puts my extreme range right at 550yds. Only now the bullet will be entering the kill zone at the top of the 15” circle instead of the bottom….

I feel this gives me a credible 3 point 550yd ranging system that is quicker than a massive range table taped to my stock, or a difficult to see jumble of lines/dots/knob markings etc. where I can easily make a selection mistake or take to long to setup. I expect to be able to reduce my kill zone size during load development as a true 500yds is as long as I plan to shoot, but 15" is a good starting point for now.

This same method can be easily used for any game you choose to target with the same load. It is a simple matter of running the MPBR calculation on a larger or smaller kill zone, following the range data to come up with a TOB hold and a max holdover point based on drop, making the zero range adjustment to the scope and head off to chase moose, deer or antelope etc.

With the money saved on an expensive BDC scope you can buy a top of the line standard scope setup with Duplex reticle to make it a slam dunk to see where your crosshairs are.

My last observation would be that this technique would work even better with a first focal plane (FFP) scope as the crosshairs would grow in size along with the target at higher magnifications opening up more possibilities to get the crosshairs right on the money. Alas, FFP scopes seem for some reason to be made of gold dust or something as I have yet to run across a comparable scope to my Leupold VX3 or Zeiss Conquest with the FFP arrangement that I can afford.

Anybody that can poke holes in this I am listening…….
Overlay your mpbr with your real world accuracy of you and your rifle. Suddenly your ethical range is drastically decreased.
I use mpbr and top of back, but I consider my mpbr based off a 200 yard zero because I want to be able to shoot offhand to 200.
I have 16 inches of drop at 400. I'm not a fan of shooting at game past that.
 
I have some setup MPBR style and others with BDC.

The Shepard dual reticle scope (one FFP the other 2nd) is the one I like the best for hunting at various unknown possible ranges. Not the best glass out there but the only one I know of with the features it has.

lots of time, where I hunt, it’s unnecessary as distances are either shorter or known.
 
Some of my longest shots were with a 270 using MPBR. It was sighted +3" at 100 yds, +4" at 200, on at 175 and 12-14" low at 400. Worked on anything that was within my capability.

The load in my Bergara B-14 6.5 CM is right on with the BDC in Vortex. I have shot it several times from 100-500 yards and each MOA mark is on. All you need is a rangefinder. Pretty cool when you can keep your shots from 100 out to 500 yards in a 6" circle.
 
I've never used MPBR. Any rifle chambered in a modern cartridge shooting pointed bullets with a MV of 2600 fps or greater zeroed at 100 isn't going to drop enough at 300 yards to require more than a few inches of daylight between the top of any big game animals back and the cross hairs to get a hit in the kill zone. And between the muzzle and about 130ish yards the bullet will never be more than 1" above or below the POA. Never more than 2-3"" low at 200 ( between the muzzle and 200 is where the vast majority of shots are taken regardless of where you hunt)

Going to a MPBR requires you to zero 2-4" high at 100 resulting in shots being 4-5" high around 200 and they only extend the probability of a hit by a few yards beyond 300. ( where you're far less likely to ever take a shot). I always figured that if I could remember to hold 5" low at 200, I could remember to hold 5" high at 350. In other words a MPBR zero makes things harder at the ranges you're most likely to shoot and you gain very little at ranges where you may never shoot.

An awful lot of shots anywhere require bullets to be placed through small openings in brush. Having bullets several inches above line of sight at close to moderate ranges makes placing those shots much harder. That is why I really like not having the bullet more than 1" above or below my line of sight at those ranges. That ability far out weighs the small advantage you get by having bullets 4-5" high at various ranges.

Out to 300 trajectory is easy to figure out. Beyond 300 range estimation is critical. If you estimate an animal to be 325 and he is really at 375 then the difference in drop is going to be enough for a miss (or a wounding shot) with even the flattest shooting cartridge. You don't take quick snap shots beyond 300 yards. You need time to use a range finder and find the exact range and then having a scope with a BDC reticle or adjustable turrets is really the only way to go.

If you don't have time to set up, find the exact range and figure out which aiming point then you pass on the shot at extended ranges. If you're not shooting beyond 300 yards you don't need anything other than a standard reticle and you don't need to zero at any range beyond 100 to make hits out to 300.

If you're talking about 30-30 and 45-70 class cartridges then that completely changes things.
 
I purchased a BDC scope several years ago with the thought I'd be able to do some western hunting and possibly caribou. I found the numbers matched up quite well for my .280 Rem with a 160 NP vs the "scope dope" built in for "30-06 180 grain," so that was the load I selected. Some time at a range to 400 yards verified that, so I was good to go...until my "ins" for the above hunts went away and I used the scope largely for whitetails and some informal PRS type shooting. For whitetail, I have a maximum practical range of 300ish yards where I hunt. MPBR, with a slightly flatter shooting load is more than sufficient for this use, but I decided to use the BDC reticle anyway, and last year it cost me a deer. I forgot to hold up a hash mark on a shot in the 200 yard range and skimmed a bullet under the belly of a small deer. Using my MPBR method, the deer would have been down. MPBR has a few caveats as mentioned in some above posts. Folks tend to use it as a shortcut to actually practicing long range marksmanship skills and techniques. IMHO, it hits it's practical limit at the 300 yard mark with 30-06 class rifles, perhaps 350 with some of the flatter shooting magnums or new super BC bullets, the reason being folks are looking through rose colored lenses and discounting the other factors that affect a bullet in flight and disperse the "perfect" trajectory that MPBR is predicated on.

Beyond 300, unless given absolutely perfect conditions and a super accurate rifle/shooter/rest, real rifleman's skills come into play, and this is where BDC, Scope dope, and Mil Dots/ auxiliary aiming points both for elevation and windage become useful tools to be combined with the rifleman's skillset and knowledge. Aiming at the right elevation to center your impact range on the kill zone will hedge your bets on a humane kill.
 
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