7MM Ultra Mag load for longrange whitetails

wrong rifle

I also use the bergers in my 7 mag, that rifle i can make them work at magazine leignth. The ultra is a single shooter. I had the two swiched around. sorry
 
A few observations I have about this discussion...

In a factory Remington 7RUM, the throat is too long to seat a 168-180 Berger at, or into the lands and still have the C.O.L required for magazine length. In fact, the SAMMI spec on the chamber/throat is too long for this, not just Remington. You will also find that loading 168-180 Bergers at, or into the lands on a factory rifle creates a C.O.L that is too long to extract without removing the bolt. A barrel chambered with a reamer cut to reduce the throat length is necessary for proper function.

Initially, you stated that you consider long-range to be 375-400 yards but many deer are at 175 yards. I have no issue with what you consider long-range to be compared to other's view of the subject.

My initial thought in your choice of bullets, distances you are shooting, and resulting lost blood trail is that you need to take into account impact velocity. I don't know what your muzzle velocities are in order to calculate impact velocity at 175 yards, but given the abilities of the cartridge to produce substantial velocities with the 140gr bullets you have been using, I will assume it is still over 3000fps. At these impact velocities, your bullet most likely isn't staying together long enough to retain energy much less produce complete penetration. This is probably why you are seeing better results with the 7mm rem mag at lower velocities. If you are set on using a bullet in that weight range for the ultra mag, it would serve you well to consider a bullet that does not incorporate a core and jacket such as a Barnes Banded Solid 140gr.

I would suggest you try bullets in the 160+ class and reduce velocities to improve bullet performance at the distances you are typically shooting or switch to a solid.

Just my $.02


Brain,
I came here to learn all I can to get the RUM to put the whitetails down as fast as the 7mag. I was just thinking that the heavier bullets were for the larger game and that I needed a fast light bullet to get the shock and knowckdown that I needed that is the reason for staying with the lighter bullet.However when I read what you said about using a heavier bullet to slow the velocity down to get better performance out of the bullet you got my attention and I am very interesed in what you can tell me you would do.I am by no means an expert and will not claim to be one,I came here for knowledge and have found some and appreciate it and would be greatly appreciated for more info on this b4 deer season comes in this year.Thank you guys very much for the help!:)
 
I come here seeking knowledge as well. The more I learn, the more proficient I can be if I can apply that knowledge in the field.

I worked in a few gun shops for a number of years off and on. Any time a new cartridge came out, some customers would line up waiting for their new "deerslayer." Others would denounce the new offering as either "too much for deer" or not any better than their "old '06." Some would take time and consider the application of the cartridge and use that for determining if it fit their needs. Many of the "deerslayers" would be on the used rack before the next season.

A cartridge in a class such as the 7mm Ultra Mag is not an average whitetail cartridge by any stretch of the imagination. Given the preferred habitat of the whitetail, and the most common method of hunting them, I would venture to guess that most shots are taken at close to medium range. I don't believe that the majority of hunters are shooting whitetail at distances approaching 400 yards. There are some hunters shooting whitetails beyond that range, but as the distance grows, the pool of shooters making, or even attempting to make those shots tends to shrink.

That being said, I have heard a lot of criticism for the ultra mag class cartridges due to extreme damage and the resulting loss of meat. When I hear comments like that, it makes me think that either the tool used for the job is not the correct one, or the operator doesn't know how to correctly apply it.

A comparison I like to make when talking about terminal ballistics (which can be understood by most individuals) is one that incorporates race cars and big rigs. Most folks who zoned out when I would try to explain ballistics to them would suddenly wake up and yell Petty, Earnhardt, or Gordon at this point.

Take a Formula 1 car zipping along at 200mph. Run it into the wall and see what happens. Due to the construction of the car, the velocity of impact, and the resistance of the wall, the car tends to fly apart, quite spectacularly, in many directions and in small pieces. The wall suffers little more than some chipping and scuff marks. Now take a fully loaded tractor-trailer weighing in at 80,000lbs and traveling at less than half the speed of the race car...run it into the same wall. Chances are, you'll be missing a few rows of seats well past the wall. While the front of the truck will sustain damage, the majority of it will make it beyond the wall while displacing most anything in its path until it comes to rest.

The same is true for shooting. A lightweight, thin jacketed bullet at high velocity is excellent for varmints and similar game as you will have the formula 1 effect on them. A heavier, thick jacketed or solid bullet at velocities less than the race car cartridge will retain more of its weight and needed energy to traverse a larger, thick skinned game animal. Energy is just as important as bullet design. Without taking both into account, you set yourself up for failure in the field.

Now back to the 7 ultra. If we are to construct a cartridge for a specific purpose such as long range hunting of whitetails, we want it to deliver a bullet, at a certain average distance, capable of quickly killing that animal. By using the same load and changing the distance to either too far away, or too close, our selected cartridge does not deliver the intended results. Too far and it lacks the energy for penetration and expansion. Too close and it expands too quickly and violently reducing penetration. There is a happy range of velocity for every bullet design.

If all I had at my disposal was a 7 ultra, and most of my shots were inside of 400 yards, I would develop loads closer to the performance of the 7 Rem mag. Why? Because at full capability, the 7 ultra will not perform as desired at those shorter ranges. In my opinion, it is somewhat of a niche' cartridge better suited, at full capability, for distances well beyond 400 yards in the hands of a capable marksman.

I'm sure there are others with a different point of view on this matter. Please feel free to add to the discussion.
 
Im new at longrange hunting and by no means an expert. I live in pa were i have a lot of experince hunting whitetails. I have used 160 accubonds at ranges 50 to 850yds and never had any problems with them. Ive hunted many yrs without longrangeing. Here even though i can harvest deer at 100yrds its nice to know that my options are open for longer shots on deer plus u can watch over more area. That was one of the resons i got involved in longrangeing.
 
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