reloads for a 7mm rum

redhunterZ71

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anyone have a good load for a 140 gr ballistic tip in a 7mm rem ultra mag. im shooting a load now with R22 90.5 gr with a 140 gr nosler ballistic tip
 

megalomaniac

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Gotta agree with Mr. Big.... the ultramags really shine with heavy-for-caliber bullets.

With your above load, you should be pushing the 140BT's around 3450-3500 fps. Heck, my little 7 WSM does 3300 fps with the same bullet (although I use accubonds in it) and a LOT less Re22. Use a heavier bullet, and fill the case up with a really slow burning powder like Re25, US 869, retumbo, IMR 7828 or the like.

The ultramags are so horribly inefficient, the only justification for their existance is to fling bullets with insane BC's at magnum velocities. Don't get me wrong, I LOVE the ultramags and the niche they fill
 

megalomaniac

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Tim,

The 140's are awesome under 500 due to thier higher speed overcompensating for the poorer BC. (Except for wind drift... IIRC off the top of my head, the heavy BC bullets are better in wind after only 400 or so).

That being said, with many ultramags, you often get more 'bang for the buck' with the heavier bullets, because of the inherent cartridge inefficiency.

IE, it takes a ton of powder to push the 140's at top speeds, while a bullet 25% heavier will travel only 10% slower with a little less slower powder. And that doesn't even take into account the extreme throat erosion you get with the ultrafast light bullets.

In my mind, there's just no reason to shoot an ultramag unless you actually plan on shooting past 400-500.
 

TiminTN

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I built mine for 1 purpose only. Antelope. It does that job well.
It is also the reason I chose a 7mm bore as the BC`s are matched higher for lighter bullets than the 30 bore.
I shoot 600 yd matches, and have a good idea of BC`s and their role in wind and drop. I think I ran the numbers to 600, and was just trying to be agreeable, but the 140 7mm is king to 600 yds, if not mistaken.
I`m talking drop, not wind. The 200 fps advantage keeps the 140 in the boiler room "better" out to 600 yds. Now I have to ask myself another question.
Just how far is my personal limit, and am I willing to use a living breathing critter to find out? Now if I were to compete with my rifle against some of the TV or DVD celebrities who shoot at extreme range, or just want to get on this site and others to brag.
I guess I could with the equipment I have it would certainly be justifiable. That just ain`t me.
If I am set up, right now out to 500 with no holdover, just a top of the back hold I`m good. You go out to New Mexico with that and look around with rangefinder and you will see that is a lot of ground you can cover.
I get excited being able to stalk, and use the territory, belive me, I have enough gun. No other bullet change for me.

I did buy some 162`s to play with, and have access to a 600 yd range, so maybe I should do some experimenting to confirm some of my beliefs.
 

megalomaniac

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I agree with you Tim on most points except for the importance of wind drift in longer range applications. For me, it's a no brainer to range, come up clicks, then pull the trigger. But judging wind speed is much more difficult than judging distance.

I might miss the distance by a yard or two with my rangefinder, but it's entirely possible I could very well be off 5mph in guessing wind speed or even in wind angle. Heck, even if you have a Kestrel, there's no guarantee that the wind is consistent from the point you shoot to the target.

I may actually be making your point for you since I won't shoot at game long range if there is more than a 5-7mph wind because of the increased variablilty, but still that being said, its so much easier for me to compensate for bullet drop rather than wind drift.

At the distances most people are willing to shoot, I will still contend that the ultramags offer no advantage over traditional magnums, though. For example, using a 7mm Rem Mag versus the 7mm ultramag and 140gr BT's, the standard magnum only drops 2.5" more at 400 and 5" more at 500 than the ultramag. And uses 25 grains less powder. And has a much longer barrel life. Why spend all the extra money in powder, brass, and barrels if you aren't going to take advantage of the cartridge (long range applications)? And if you are going to shoot long range, the heavier, higher BC bullet will shine in KE and wind drift.
 

mr.big

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Tim I know you know your stuff,,I just couldn`t get the 7RUM to shoot accurate with the lighter bullets and muzzle blast was horrific,,I could get the 154 Hornady within 50 FPS of the 140 and the 162 was no more than 100 slower,,

with 140 7mm bullets the Weatherby or STW is about all the powder you need..
 

TiminTN

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I would expect my case to push a 160 to 3400. The 140 will run 3650. I`m sure my case is more efficient than the 7mm RUM and is the reason.

I use 88 grains of 7828, and never blink at the thought is is this or that many grains more than a 7mm Mag. This all has been a constant learning curve for me, and had I had experts advise me many years ago, I might have gone a different course, but I didn`t, and have done the best I know how.

My 7mm/338 to me is the finest rifle I ever came up with. It was from direct experience from a friend building Raptors with Tim McWhorter using RWS 404 Jeffries brass.

When the Ultra Mags came out, I was hoping I could get me one that would fit as well as the Raptor and its 2.5" case length. If I had a full bore 7mm Ultra, I`d probably run 160`s too, but my case has been delightfull with the 140`s.

This will drive megalomaniac crazy, but will say it anyway.

I don`t use clicks yet to hit distant targets, so holdover is my way and the "look no hands" method for me is best suited for a guy who shoots as flat shooting a rifle as possibe.

Now then, to use dials, the rifle can be a slug, and just wind on the dials a bit more and ta da, you are there.

So why do you need a Ultra Mag and a 200 grain bullet to shoot 600+ yards?

Seems a 7/08 or 30/06 with dials would use so much less powder. This mentioned since powder consumtion was a high regard for you.
 

mr.big

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thats exatly why I used the 300 RUM and 150 Partitions for 7-8 years,,to the edge of my shooting ability I could hold on hair..in this part of the country its rare to be able to see past 450-500 yards.
 

mr.big

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how is the Raptor different than the 7 Dakota???

I don`t do clicks either,,I can look through the 3.5-10 and get a pretty good feel if its inside 500 yards or not,,if not I don`t shoot if soo I feel pretty good about the situation..

even though if I had the money and time I would try to get the equipment to learn to go farther,,as it is now I can zero dead on at 300 with the 300 RUM and 150`s and just shoot to 500..
 

megalomaniac

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TiminTN said:
So why do you need a Ultra Mag and a 200 grain bullet to shoot 600+ yards?

Seems a 7/08 or 30/06 with dials would use so much less powder. This mentioned since powder consumtion was a high regard for you.

Personally, I like the ultramags and heavy-for-caliber bullets for the significant improvement in wind drift and very high retained kinetic energy. I know, I know, whether you hit a deer with 2500 ft-lbs of KE at 600 yards vs 750 ft-lbs at 600 yards will not kill a deer any 'deader', but it does seem that they end up 'dead' just a little quicker! So you don't 'need' them for the improved bullet drop, but the decreased wind drift is huge.

As far as powder and barrel life of the ultramag cases, honestly I could care less; I realize I'm being wasteful. But to others on a tighter budget, it IS a factor to consider.

BTW, I use the 'hold over' method on all my other shorter range rifles (shots 400 or so and in). For me, I just can't judge a 48" hold over, or 12" windage on the longer shots and feel as comfortable. I'm not saying using clicks for come-ups is the only way to do it... just that for me it is easier and I feel is more accurate. It also ensures I don't forget to compensate for windage in the heat of the moment.
 

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