How do you select the right bullet for long range

[EMorr]

Sorry in advance for the long post. I think it would be safe to say that the vast majority of people get into reloading to the best bang for the buck out of their rifle. What that means to different people is obviously different, some may reload to save money, some may be looking for a hobby that goes hand in hand with the shooting sports and others still are looking to get the upmost performance out of a specific cartridge. For those who hunt bullet selection depends a lot on the type of game they will be hunting. For the target shooter bullet selection has a lot to do with the distance at which the shot is being taken.

I think one of the first things those new reloading learn is that the higher the ballistic coefficient the better the bullet will slice through the air. Not always but most of the time gaining a higher B.C. means the bullet will be heavier and longer. While this is not always the case, it holds true especially when the comparing a bullet with a B.C. of .250 to say a bullet with a B.C. of .600. Taking the aforementioned as a given the bullet with a higher B.C. will then be heavier, with all other things being equal (Yes I know that all other things are rarely equal in the real world) that bullet will then have a slower Muzzle Velocity but will retain its velocity and therefore kinetic energy down range courtesy of its higher B.C.

Okay so I’ve covered what all of us already know “Higher B.C. = good for long range shots.” My question thought is at what range do you make the switch from light fast moving bullets to the slower, heavier bullets that are better for long range? Do you base it solely on the range you shoot at or do you guys consider TOF, bullet drop, Impact velocity, Kinetic energy at target, windage adjustment needed and other factors that I have not mentioned.

As an example of why I am asking this question, below is the information from a ballistics calculator for one of my hand loads and the FGMM offering for 30-06 both at 1000 yards and 10 MPH of wind.

FGMM
Drop : 327.62 Inches
MOA ADJ : 31.28
Windage : 76.42 Inches
MOA ADJ : 7.30
Velocity : 1418
Kinetic Energy : 750 ft-lbs
TOF : 1.54 seconds

My Reloads
Drop : 363.36 Inches
MOA ADJ : 34.70
Windage : 61.86 Inches
MOA ADJ : 5.91
Velocity : 1484
Kinetic Energy : 1017 ft-lbs
TOF 1.59

As you can see the FGMM wins in the bullet drop and adjustment departments as well as TOF and is very close to the same velocity as my own reloads obviously the kinetic energy is down though. My reloads win in the windage and kinetic energy department. If one bullet grouped better out of my rifle at 1000 yards that would be the clear winner as they are fairly close on everything else. But at this point it is all theoretical I hope to one day get to 1000 yards but am not quite there yet, however I want to be prepared and one way of doing that is to know how and when all of you select your bullets for long range shooting.

In other words which bullet would you choose, at which distance do you make the change to the heavier bullet and why? I am not solely interested in 30 cal bullets as I am just getting started and will add other calibers as I go so I would be interested in hearing from shooters of all calibers. Thanks in advance for your thoughts on the matter.

 

[427Cobra]

Re: How do you select the right bullet for long range

Heavies buck the wind better, and have more retained energy at distance comapred to lighter bullets, so just shoot the heavies.

 

[Ratbert]

Re: How do you select the right bullet for long range

Figure out what the max range you want to shoot to and then what range will encompass 90% of your scored targets. First check to see if each round will be able to remain supersonic to the max distance. If one won't, use the other. Then look at wind drift comparisons for the two rounds out to whatever range you will shoot most of your scored targets to. If there is only a tenth or two mRad difference between them to that range then it's pretty much a wash and go with whichever you like (the lighter will probably be cheaper to shoot, easier on bore life, and have less recoil.) If not, shoot the heavier one.

Or, you know, just do what 427Cobra said. Depends on how much you consider over-analysis a hobby.

 

[MALLARD]

Re: How do you select the right bullet for long range

drop and drift are just numbers, they don't tell the whole story.

you really should shoot the bullet that your gun likes the best. If you had two bullets that shot equally well , well then you got some thinking. If one of those loads has a better ES/SD , or was less temp sensitive, then you should shoot that load.

if you dive deeper into the depths of reloading chances are the FGMM will not hold weight to your reloads. You can meplat trim , sort , and point your bullets , something an FGMM shooter can't do. You'll raise your BC while more importantly uniforming your BC , less BC variation = small groups downrange.

why are you not shooting at a 1000y right now ? could you not get on paper or something ?

 

[Ratbert]

Re: How do you select the right bullet for long range

The thing that has always gotten me about metplating is that, sure you raise your BC and you uniform it but you no longer have Bryan Litz's doppler radar derived calculation of what the BC actually is. If you're shooting F-class then I suppose it doesn't really matter but I really like that JBM can pump out charts for any density altitude and distance I need and using Bryan's data I have been pretty much spot-on so far out to 1350 yds.

And sure, if you can't get VLD's or JLK's to shoot with your throat using the length you want then you obviously shouldn't use them. But I think it it is implicit to his question that he'll be using two loads that appear to work favorably in his gun, he wants to know how to evaluate differences in ballistic performance at range of different classes of projectile, not asking how to do a OCW test. Besides, I just don't buy the whole mythos regarding guns "liking" one bullet over another. If your gun can't shoot a 175SMK or a 139 Scenar or any one of a dozen other bullets that have been repeatedly built into very high quality factory ammo then there is either something wrong with your gun or something wrong with your method of loading for it. IMHO, this is more a case of people shooting a very small sampling of two different loads, picking whichever 5-rd group happened to look better that day and then declaring their gun "liked" that bullet better. Some guns might not be setup to shoot some types of projectiles because of throat length or other requirements and some projectiles might be more finicky to load for than others but that is still a discussion regarding individual loads performing in individual guns, not about selecting which class of bullet to design a gun and load around.

 

[Tripwire]

Re: How do you select the right bullet for long range

My last build started with the rifle being built around 190 SMK as the primary bullet, with the hope that the 208 Amax would shoot as well. Haven't tried the 208's yet, but that will happen at some point. The rifle shoots the hell out of the 190 SMK.

I like the heavies in any chambering, with a high BC, for the obvious reasons. My theory is, they work just fine at close range too......

 

[targaflorio]

Re: How do you select the right bullet for long range

http://02b0516.netsolhost.com/blog1/?p=186
or just ask Bryan Litz

 

[EMorr]

Re: How do you select the right bullet for long range

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MALLARD</div><div class="ubbcode-body">

why are you not shooting at a 1000y right now ? could you not get on paper or something ? </div></div>

I have not been able to shoot to 1000 yards yet due to the fact that until recently I was limited by the built in elevation adjustment in my scope. I was also limited by the fact that the only semi-public range near me is only a 650 yard range. I recently added a 20 MOA base to my rifle and hopefully will be able to join a private range that is not too far from me that stretches out to 1000 yards. With those two changes I hope to move to and one day pass 1000 yards.

 

[MALLARD]

Re: How do you select the right bullet for long range

I have not been able to shoot to 1000 yards yet due to the fact that until recently I was limited by the built in elevation adjustment in my scope. I was also limited by the fact that the only semi-public range near me is only a 650 yard range. [/quote]

the scope reason makes allot of sense, what kind of scope are you using ?. If you put one of those single shot loading blocks in your gun would they let you shoot at a closer 1000y ranges ?

 

[EMorr]

Re: How do you select the right bullet for long range

My current scope is a Leupold VX-II 3-9 X 40MM. After tax time that scope will probably find a new home on my flat top AR. I will probably then upgrade to either a VX-3 CDS or Mark 4 LR/T scope with a slightly higher max magnification and a 30MM tube for more built in adjustment.

 

[crewchef]

Re: How do you select the right bullet for long range

I make the swap at anything over 600. At 300/500/600 I shoot Sierra 175 SMK. Anything further and I shift to Berger 185 LR HPBT. If it's an "important" match or forecast of breezy condiditions might use the 185's at 600 too.

 

[QuiggyB]

Re: How do you select the right bullet for long range

A lot of people shoot a smaller caliber / lighter bullet at 600 and below because its cheaper, better barrel life and less recoil which contributes to accuracy. The difference in performance at those ranges in a lot of cases can be fairly minimal. Past 600 they generally shoot the heavier bullets and a lot of times use a more substantial round. An example would be using a 6BRX for 600 and below and a 7MM short mag of some flavor for 1000 yard.

 

[QuiggyB]

Re: How do you select the right bullet for long range

For comp shooting I think generally all that matters is consistency of performance and wind drift. The amount of drop isn't a big deal because its dialed out. But getting consistent velocity shot over shot is a big deal because it gives you the largest scoring ring.

 

[dwt]

Re: How do you select the right bullet for long range

Lots of range work will answer most of your questions