Different Caliber - Similar Ballistics

338winmag

Handloader
Jan 9, 2011
369
0
I have been wanting to ask this question for some time now. (If I have asked it before and forgot about asking it, attribute that to getting old) :lol:

7mm Rem Mag; guestimating the ballistics of 2 different weight bullets (Using JBM web page calculations):
Partition 150 gr
400 yards
-16.5 drop
2512.0 fps
2101.3 lbs energy

Partition 160 gr
400 yards
-17.9 drop
2422.6 fps
2084.7 lbs energy

Question 1:
Aside from the obvious numerical value differences, what if any is there a benefit of using a heavier 160 grain bullet to the 150 grain bullet?

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7mm Rem Mag vs 30-06 and guestimating the ballistics and comparing the guestimated results (Using JBM web page calculations):
7mm Rem Mag - Partition 150 gr
400 yards
-16.5 drop
2512.0 fps
2101.3 lbs energy

30-06 - Partition 180 gr
400 yards
-20.2 drop
2283.9 fps
2084.5 lbs energy

Question #2
Does not the power and benefits of the 7mm rem mag appear to be more powerful with a 150 gr bullet than the 30-06 with a 180 gr bullet in the questimated ballistic senario such as thie one above?

I get a bit confused because I see that some prefer the heavier bullet for certain calibers but from what I can discern, heavier is not always better?

Is there something that is not seen in the guestimated ballistics equation but is seen in real life scenarios (which then kinda negates the science of ballistics? :?

338winmag grasshopper :mrgreen:
 
Question 1:
Aside from the obvious numerical value differences, what if any is there a benefit of using a heavier 160 grain bullet to the 150 grain bullet?
My Opinion: Since you cited an example using the same caliber and bullet example - The SD and BC is greater with the heavier bullet. If you are shooting 200lb or less deer at 300 yds and less, I don't believe their is a deer breathing that could tell the difference. If Elk or any animal that has bigger bones / muscle mass then the added weight gives you more confidence of having enough bullet left after hitting bone.
Any time you are going longer distances with your shot the BC becomes more important. Don't forget that wind deflection left or right becomes a large variable to contend with and the greater BC of the heavier and longer bullets defiantly will help.
At the end of the day with the Nosler PT - which one does your gun like?

Question #2
Does not the power and benefits of the 7mm rem mag appear to be more powerful with a 150 gr bullet than the 30-06 with a 180 gr bullet in the questimated ballistic senario such as thie one above?

I get a bit confused because I see that some prefer the heavier bullet for certain calibers but from what I can discern, heavier is not always better?

Is there something that is not seen in the guestimated ballistics equation but is seen in real life scenarios (which then kinda negates the science of ballistics?

One thing I've learned - Deer are easy to kill. Elk are NOT impressed with ballistics / numbers. You have to HIT them right with a properly constructed bullet and then they will be in the freezer. I've seen them drop with a 243 and seen them make a mile or better with a 338 that I can not explain how. Most field scenarios can not be modeled with math. Just use good shooting skills for shot placement and use the right bullet for the task at hand, which ever caliber you choose.
 
One important thing that you didn't include was muzzle velocity - it's interesting to see how a heavier bullet sometimes "catches up" with a lighter bullet that was initially launched at a higher velocity.

All else being equal, heavier bullets also tend to penetrate deeper - but not all things are equal of course. I've been downright impressed with the penetration of small, light bullets of mono-metal such as the Nosler E-Tip or the Barnes TSX.

Wind drift is something that the heavier, higher BC bullets tend to deal rather well with - and at longer ranges wind is the bugaboo of the rifleman, not elevation. Elevation problems are usually pretty easy to deal with - not so with windage. This is why long-range target shooters usually opt for longer, heavier bullets - to keep the bullets from straying out of the bull from an errant breeze.

Heavier bullets though are NOT always better - I for one think that deer sized game often falls faster to smaller, lighter, more frangible bullets. That may be the evil influence of too many years of seeing the results from various .24 & .25 cal rifles.

Interesting subject.

Guy
 
Excellent answers Teknys and Guy.

One answer hit me right away that had failed to keep in mind.
"If Elk or any animal that has bigger bones / muscle mass then the added weight gives you more confidence of having enough bullet left after hitting bone." Good thinking Teknys!!

Also I guess I am a little tunnel vision with honestly not believing I would ever take a shot past the 400 ish range, but those that will, the heavier bullets most of the time reflect a better BC for those trajectories and cross winds. Again good thought Guy!!

I do look at the BC and the SD but again, with my thinking of inside 400 range, I did not weigh those numbers to factor in that much but as the first two replies pointed out, there is a reason and purpose for those heavier bullets.

"Elk are NOT impressed with ballistics / numbers" --> Darn those uneducated Elk!!!

Thank you shooters!
Steve
 
For deer, I have had better luck in DRT performance with the 160 Partition, 7mm Rem Mag over the .30-06, 180 grain. The 7mm, 160 gr kills deer like lightning, even at 300+ yards. Mind you that I normally use a .270 Win for deer and have only killed maybe 12-15 with these two calibers, most of them with the 7mm.

For elk, I had bad luck with the one elk that I shot with the 7mm Mag, a factory 175 gr bullet failed to penetrate on a shoulder shot and I lost the elk. However, I like more caliber for elk and have used a .338 variation for most. The one that I killed some years ago with a 180 gr Partiton, .30-06, died within 30 yards or so when shot at about 100 yards range.

BTW, I have not had much luck getting smaller caliber bullets to fly according to their posted Ballistic Coefficient at 300 yards. Factory BC's are pretty optimistic for bullets that are flying less than 2500 fps. This is true of both 7mm and .308 bullets that I have actually measured drop on when I shot at a 300 yard range.
 
Some good and very interesting experience comparisons Oldtrader3.

I am primarily hunting mule deer\elk with my 338winmag. The 7mm rem mag is a backup but I am also loading for a 30-06 and 300 win mag this year as well and possibly another 7mm rem mag for the hunting camp. When researching, that is when I noticed again how the "book" values sometimes contradict the pecieved bigger is better.

Our entire camp is hunting with Nolser this year. Everyone will be using Partitions with the exception of my 338winmag using Accubonds.

Thanks all
Steve
 
Steve, I think that many average hunters would rather not shoot a .338 WM, despite all the hype about this caliber on elk killing performance. I bought my .340 Weatherby Mark V (cheap) from a man in Georgia and it had been owned by two people and had only one box of ammo through it. The guy that I bought it from had never fired it. Out west here we have a lot of long range shooters using .338 Lapua's, .340 Bees and .338 RUM's for long range shooting.

Even here in Washington, despite being an elk hunting state, there are not a lot of .338's and .340's etc. for sale in the local gunshops and when you see one, it is usually on sale. I think in reality, medium magnums are not big sellers and except for maybe .375 Ouch & Ouches and don't move all that well. When I picked up the .340 some years ago at my local gunshop, the concensus was among the clerks asking: are you going to shoot that thing much?

I think that for most hunters a .30-06 or maybe a .300 WSM is about the limit that they want to shoot on a regular basis. I do not see any .338/.340's at my gun club which has 1800 members, except for me.
 
Yeah I only see a few 338winmags over here in Colorado. I luv mine and go to the range with it often. If it is because of recoil, I can understand for some. At the range off bags or off-hand I start to anticipate recoil around 13-15 rounds. If using the Lead Sled, I can shoot all day with it.

In the hunt, I never feel a single thing (must be the adrenalin) Same thing goes for my 12 gauge 3 1/2" magnums. When shooting at ducks and other game, I never notice a thing but my laughing as we are getting our bags. :) :)

Thanks
Steve
 
"In the hunt, I never feel a single thing (must be the adrenalin)"

Could be. The last elk I shot at with my .300 Win. mag. was a very long 530 yard affair laser measured. That was 8 years ago BTW but I still remeber it as if it were yesterday. It was about 8 in the morning and the herd was at one side of this very large "park" and me on the other side. I managed to stalk to the very last bit of cover, lasered the elk and from a sitting postion sent a 200 gr. Speer Hot-Core down range. I shot the last cow in the line and at the shot, she went down, kicked a bit and expired. I only have two loads for that el cheapo Winchester M70 that was a Walmart special for $350. Both loads use the long discontinued WMR powder and the bullets are the 200 gr. Speer mentioned and the 200 gr. Nosler Partition. The loads are such that I can switcch them and not worry about any significant change in trajectory. Usually the magazine is loaded with the Speer load and a Nosler load is up the spout. If I get a shot to 200/250 yards the Nisler gets used but if it's a much longer shot, I replace the Nosler with the Speer and go from there.
Now about never feeling anything. When I took that shot, conditions were perfect. No wind at all. The shot sounded like, "Poof." If that rifle kicked at all, I never felt a thing. Maybe it was adrenaline but that's what causes buck fever. I'm more inclined to thing that I was so concentrated on making that shot that the recoil and noise did not exist as far as my brain was concerned. I pretty much noticed the same results with a .270 Win. when I shot my antelope in 2009.
As far as the .338 Win. mag. goes, I have two. One a 1968 push feeder which I can almost tolerate recoilwise and a Stainless Classic that is the worst POS I have ever owned and I'ved owned a few lousy guns. I'd put that one on my table when I do a gun show but that would violate my ethics. I think the problem is that cheap tupperware piece of crap they call a stock.
I do have a McMillan in the Featherweight configuration and it's no lightweight so maybe with a Decellerator recoil pad and a decent glass bedding and trigger job, maybe that POS will do better than 5 and 6" groups. I'm of the thought that trying to make it shoot better may not only be a gamble but a total exercise in frustration. :roll: Too bad bcuase it's a really neat rifle otherwise, if you like decorations on the wall. :roll: :roll: :roll:
Paul B.
 
TENKNEY'S on the mark with both answers.

Paper ballistic numbers do not take in the fact larger diameter bullet make larger wounds than smaller diameter bullets. Bullet with larger Section Densities penetrate deeper than bullets with less SD. And heavier bullet derive more of their momentum from weight which stays with them as velocity decreases. Remember even if the shed some weight its not shed by a square as velocity is (mass times velocity squared). So you see you can afford to lose a little mass but it really hurts to lose even a little velocity (if you a light bullet).
 
tjen":1qodcfzr said:
TENKNEYS on the mark with both answers.

Paper balistic numbers do not take in the fact larger diameter bullet make larger wounds than smaller dia bullets. Bullet with larger Section Dencities penitrate deeperthan bullets with less SD. And heavier bullet derive more of their momentum from weight which stays with them as velocity decreases. Remember even if the shed some weight its not shed by a square as velocity is (mass times velocity squared). So you see you can afford to lose a little mass but it realy hunts to lose even alittle velocity (if you a light bullet).


I agree with all,,,,
Specially where added mass maintains more momentum throughout the animal.
 
#1 The heavier 160 gr PT will penetrate deeper than the 150 gr PT.

#2 The 30-06 doesn't give up that much to the 7mm Rem Mag.

JD338
 
"One thing I've learned - Deer are easy to kill. Elk are NOT impressed with ballistics / numbers. You have to HIT them right with a properly constructed bullet and then they will be in the freezer. I've seen them drop with a 243 and seen them make a mile or better with a 338 that I can not explain how. Most field scenarios can not be modeled with math. Just use good shooting skills for shot placement and use the right bullet for the task at hand, which ever caliber you choose."
I would to add , that for the most part, this pretty much covers it.
Only thing I could add to it is in ragards to this,,"I've seen them drop with a 243 and seen them make a mile or better with a 338 that I can not explain how."

I often contend, the animals mental state plays a big role.
One that is alerted, has adrenaline flowing for whatever reason, whether it be hunting pressure, fighting, or breeding ect., they can do things that make you wonder, no matter what they are hit with. Unless relaxed, most anything can happen. Worst I seen, was a pushed Elk Bull go better than a 400 yds., with no heart left, taking 2 direct hits witha 30-06 180 gr. hit at around 65-75 yds. And then have seen them hit when unaware, take .45 Colt/270 from at 30 yds., just stand there a second or 2 as if nothing had happened, then colapse. The Colt load at nearly a 1/3 of both speed and energy, gives pause for thought.
 
What are your figures for 30-06 with 150 Partition? Paper ballistics for the actual velocity I can get from
my 06 with 150 and 180 BT's give the 150 the advantage over the 180's from 400 yards and beyond.

Haven't tried the partitions.
 
Thanks for not jumping on my spelling. Seems I can't see my own errors and usualy do not have the time to look up some words. Thanks again.
 
No worries there tjen,,,don't many of us here have english/grammer degree's, I believe.
99.9% of my edits after posting are doing some corrections of such,,,and then most times, more than one edit.
Besides,,,it's the DK's fault! lol
 
Tjen, don't you have spell checker? The reason that I ask is, despite making many typos myself but I do often use a spell checker to help. I am also a lousy typist. However, sometimes I can not understand what you are trying to say because your syntax and spelling is so full of errors. That is why I have mentioned this to you about content and spelling. It is not a couple of typos, it is context which is nearly unreadable sometimes. Most people look past their errors but concise communication on a technical issue is important.

You work as an Engineering Tech or something, you should know this already?
 
No its my work PC and is update and limited to what ever the is loaded on it from the company network.


Back in the window 95/97 arra we mantained our own lap tops loading any and all programes we needed to do our jobs. Now we have no admin rights we only request things. Individual departments used to buy their own PC to best fit their requirements. Now those who do not know what we need tell us what will be best, The joy of working for big companys.


I received a ring with my degree I am not a tech And this not a report just some thing to do for fun.
 
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