ballistic coefficient

[Broz]

Well LTLR, I can see what you are saying, and didn't realise you used hold over reticles. I tend to think in the ways it works for me and I simply hate any kind of hold over. I guess one of the things I like most about LR hunting is I have time to make the shot. Growing up in the midwest and crawling in with a shotgun an slugs, or having to take that fast shot in heavy timber sucked. Now I relax and take my time. This is why I love to practice first round cold bore shots. I like the "slow hit is better than a fast miss" scenareo.


Well, I guess I need to see it for myself, cuz I just am having a hard time wrapping my mind around it. I have never been one to believe something just because a computer program said it was so. One little error in inputted data and it is all for not. So I want to shoot along side some of these bullets in the wind. Then see who is dialing less wind drift, that is what I need to see before I change what I have working so well for me in the field. But I probably would not use them anyway, I have had to many problems with solids not expanding on game , and coppering the heck out of my tubes. I know all tubes are different, but I baby my barrels and more cleaning is not what I want.

Jeff

 

[Long Time Long Ranger]

Whether I use clicks or ballistic reticles depends on the situation. But I have that option with the faster bullet. Most every year I take animals out to 600+ yards I wouldn't have if I had to turn clicks. Seconds count in the field hunting and not so much target shooting long range. Those shots are very easy with the right reticle and just gives me another option. At long range when the drops get to be 35+ inches every 100 yards turn clicks and be accurate. I do not hurry shots and wound animals however ballistic reticles with fast bullets out to certain ranges give me another option. Like I always say I want the best opportunity to have success on the hunting trip when I see the animal no matter what the situation. So I try to come up with equipment that provides me with that best opportunity. Most of my hunting is within 1000 yards with backpack gear so I gear up for my best chance within those parameters.

Your set up is good for what you do which is sit back with a top rangefinder and accurate rifle and take the time to make extreme long range shots. Just saying all I did so you understand why I do what I do. I have some extreme long range cannons for shooting the way you do but I only hunt with them when I have a vehicle to haul them around and have a means to get the range.

I just ran some numbers for your rifle on JBM with the 300 Berger hybrid against the 260 Cutting edge. I gave the 260 grain 3000 fps and yours the 2740 fps I think you listed. I have no idea if the numbers are accurate on either bullet since I have not shot them. But assuming they are the 260 will outshoot the 300 in the wind by several inches and 112" drop to 1500 yards at my 5000 feet elevation. Like you I would like to test them side by side. I don't own stock in either I just want to know.

The fouling is not an issue with the copper bullets since they figured out the cute little grooves that collect the residue instead of squashing it into the barrel. Either of these 338 caliber slugs will kill anything placed through the chest of an animal. Both have sufficient energy at any range a person could hit something.

One of the critical things you have got to look at is what distance your bullet is actually in the kill zone at a particuler range. The faster the bullet the longer you are in the kill zone. Arbitrarily say you shoot a 12" group at 1500 yards and the bullet drops 12" every 8 yards. Say the 260 gives you 12 yards through the kill. Now you have increased your odds of a kill by 33%. Again these figures are arbitrary and I have not run them just an example. You had better be dead on with your range and have a bullet that gives you the longest flight through the kill zone as it drops through it. Again I shoot what I do to give me the best chance at hitting and killing my target.

 

[Scot E]

LTLR,

Curious about what style of drop reticle you use, BDC or graduated?

Scot E.

 

[Long Time Long Ranger]

I have shot mil dot reticles for many years. However the past few years companies are coming out with 1 moa or .5 moa hashes that are absolutely awesome for quick target aquisition and hits. Get the ones with definite measurements and not the ones that have arbitrary hashes based on general trajectories. With definite hashes like a mil dot or 1 moa you know exactly what you are doing at any time with simple math.

I will just add that the 1 moa reticle hashes are a lifesaver on the alsaka tundra or any area where your rangefinder can't aquire a target. With 1 moa hashes and knowing your target size it is easy to get the range close enough to make a hit out to 800+ yards.

 

[Long Time Long Ranger]

Broz, Maybe I can get a day to drive up and we can just test some of this stuff and see what happens. Weather is bad and can't shoot right now so have some time to run JBM numbers. I would enjoy shooting with you guys up there.

I just ran my 338-378 wby shooting the 225 cutting edge D62 bullet to 1500 yards compared against your 338 Lapua data with the 300 berger hybrid. At 1500 yards JBM shows I am 4" better in the wind and drop 250" less than your current load. I have shot mine to 1500 yards destroying an elk silhouette but have not shot the 300 berger hybrid so can't say for that one. But I know the 225 data is accurate.

That puts the load I am now using 1 click better in the wind and 67 clicks better on drop at 1500 yards. Plus I am in the kill zone at that range several more yards having 225 more fps at that distance. Be fun to check that and see if jbm is on.

 

[Scot E]

I have shot mil dot reticles for many years. However the past few years companies are coming out with 1 moa or .5 moa hashes that are absolutely awesome for quick target aquisition and hits. Get the ones with definite measurements and not the ones that have arbitrary hashes based on general trajectories. With definite hashes like a mil dot or 1 moa you know exactly what you are doing at any time with simple math.

Our shooting styles are very similar. I use a 1/2 mil hash reticle for shooting out to about 600 yards, where quick shots are most often needed and atmospheric conditions don't affect bullet flight enough to worry about. Beyond that distance I use a chart or ballistic program and dial my turrets for a more precise shot. Works very well for me to cover any situation I may come up against.

Scot E.

 

[brentc]

I will just add that the 1 moa reticle hashes are a lifesaver on the alsaka tundra or any area where your rangefinder can't aquire a target.

Ain't it the truth. Reticle measurements have got me out of a jam several times in nasty tundra weather.

 

[load]

some people put bc above all else as you can see from many of these posts. however if a bullet wont shoot out of your gun ( which is the case for vld bullets and many guns) than you might as well just throw rocks!
the best thing to do is try different bullets and see what shoots best. if you loose a few moa in elevation or windage but your patterns are tighter than you have a winner.
for example berger 210 grain tacticals do not shoot well out of my rifle but the longer bearing surface of the 225 grain hornady match does the trick, switch to the 230 grain tacticals and the pattern opens up again, not as much but it does. one way i gain velocity with roughly the same bc but loose accuracy the other way i gain bc but again loose accuracy.
i'll go with the accuracy over these two situations every time. as long as your velocity and bc combination gets you to the range you wish to shoot than accuracy counts more than bc and velocity gun)

 

[Broz]

LTLR, my muzzle velocity is 2800 avrage. 2795 to 2805 to be exact @ 4100 ft of elevation and tested for drops to 1709 yards repeatedly, to 2000 plus occationally. So your estimations are a little off I am sure 60 fps would make some difference and it would be a little more at 5000 ft. Do you really think I could push 260's to 3000 fps?

When ever we get the chance we need to shoot together. It would be interesting. We could compare the 300's to your 260's in like conditions with a few groups at 1500 and 1700 yards. But they should be compared in somewhat like chamberings, not a 338-378 to a 338 LM

All the solids I used had the groves (3) in the bearing surface. ( Barnes) copper fouling suckers for sure, some barrels way worse than others.

Jeff

 

[Broz]

I just ran my 338-378 wby shooting the 225 cutting edge D62 bullet to 1500 yards compared against your 338 Lapua data with the 300 berger hybrid. At 1500 yards JBM shows I am 4" better in the wind and drop 250" less than your current load. I have shot mine to 1500 yards destroying an elk silhouette but have not shot the 300 berger hybrid so can't say for that one. But I know the 225 data is accurate.

That puts the load I am now using 1 click better in the wind and 67 clicks better on drop at 1500 yards. Plus I am in the kill zone at that range several more yards having 225 more fps at that distance. Be fun to check that and see if jbm is on.

Comparing a 338-378 to a 338 LM is not aples to apples. Plus if you give my rifle the 60 fps you shorted it and add a little for the 900 feet of elevation you have above me , I am bettin the wind drift thing just went in to my favor.

You must really be bored today.. Shut off that **** computer program and lets go shoot so we can see what really happens. Where we are not relying on the numbers that may be right or may be a fairytail. Simply shoot in the same wind and see who has the most drift. And don't forget that 338 with 225's. That way you will have all the velocity you can get...

Take care

Jeff

 

[Long Time Long Ranger]

I agree and I am bored today. Terrible weather and couldn't shoot. Had everything ready to go and just sat here. I was just running the numbers of the 338 I made the 1130 yard kill shot with this year with the 225's to see how they compared to yours. Didn't mean anything by it, just curious. Had no intention of it being apples to apples. You can run it and see what you get. I hunted at 3510-3520 fps with a .64 bc 225 grain. I have since dropped it to 3450-3460 fps and have much better brass life. At the hot load I was five shots and done at $3 a pop.

I have not shot the 260's. But judjing what my two 338 Lapuas do with 250's and the 265 barnes I am confident you will get 3000 fps conservatively. And mine are 26" barrels. I was getting over 3000 fps with my 340 wby 28" barrel and 250 sgk in 1979. My lapuas hit just over 3100 fps with the 250 easily so you should be able to shoot the 260 at 3000 fps. You have a good load and don't like copper so really no need to change for 200 fps.

 

[Broz]

. You have a good load and don't like copper so really no need to change for 200 fps.

I agree, if this was only a 1000 yard rifle the change would be pretty easy. But the amount of time I have spent to get multiple groups to double check confirmed drops at many distances out to 1700 yards and beyond is signifcant. Plus, if all the stars align and I decide to take game at avery long range I am confident I have the best bullet for the job.

But it is interesting to compare notes and opinions. I like the fact that many of us are shooting different bullets. That gives us something to compare when we do meet up and shoot long range.

Jeff