Kenetrek Boots

6.5 PRC vs .280AI

For trajectory purposes I prefer to hunt with something that has a muzzle velocity near 3000fps or more. I know everyone says “rangefinder and dial your scope”, but whether you’re dialing or holding, and whether you’re using a range finder or your eyes, there is error in all of it. The flatter your trajectory less sensitive your shot is to all of those errors. If you actually compare a .308Win with a 180gr Partition to a 26Nosler with a 140gr Elite Hunter the difference is stark.

.308Win 180 Partition 2600fps
100yd zerp
480yds -57.82”. -47.09”
500yds -64.47”. -53.30”
520yds -71.58”. -59.

26Nosler 140 Elite Hunter 3300fps
100yd zero. 200yd zero
480yds. -29.97”. -25.11”
500yds. -33.42”. -28.36
520yds. -37.08”. -31.82”

So a 20yd ranging error is resulting in a 7” difference in POI with the .308Win compared to a 3.5” difference with the 26Nosler. Also, you literally had to dial half as much with the 26Nosler, resulting in less chance for error. You compound that with the error in angle calculated by your range finder, the fact that a lot trajectory calculating range finders don’t use your actual BC, but just one that’s close, the fact that most manufacturers BCs, especially G1 BCs are fairly incorrect, the fact that your “custom dial” was set for a certain elevation and temperature that you’re not actually hunting at etc. and all this range and dial stuff isn’t as fool proof as we pretend it is, and shooting a cartridge/bullet combination with a flat trajectory is as valuable today as it ever was. Yes I choose two extreme examples, but statements are FREQUENTLY made on this forum that suggest that as long as you have a range finder and a custom turret you can make perfect hits at any range with any cartridge regardless of trajectory. It’s flat wrong. It works ok at the range because the range is always at the same elevation and the targets are usually at the exact same range and angle. Heck, I don’t have as good a hold on an animal as I do at the range. Why would I want to introduce other problems I could avoid? My personal preference is to get as close to 3000fps as I can.

Now I will finally answer your question.

A 6.5mm 140gr projectile is on the light side for elk, especially if you’re considering shooting one at a distance at which error will be greater. Sure, a lot of elk have been killed with a .243Win shooting a 100gr bullet, but most of them were with near perfect shots. If you’re going to be trying to do that at 500yds, You really want a bullet that will be a little more deadly in case of a less than perfect shot. A 6.5PRC under normal circumstances will push a 140gr bullet at about 2950fps, so for my preference, it’s pretty much topped out at 140gr. Compare that to a .280AI. A .280AI will push a 168gr bullet about 2950fps. In VLDs the 168gr 7mm has a higher BC than the 140vr 6.5mm. Depending on the manufacture BCs may end up about the same. If you’re going to shoot elk, why not hit it with 20% more bullet, especially since you have not sacrificed trajectory, BC, or impact velocity? You can wring a little extra from both cartridges with longer barrels, bullet coatings, and hand loading up to pressure signs. If you will accept a lower velocity, you can still only get to 156gr in the 6.5PRC, and can almost match that trajectory with a 175gr in the .280AI. If trajectory does not matter to you, you can go over 190gr in the .280AI.

I’m going elk hunting this year with a 6.5-257AI shooting 156Elite Hunters at 2975fps. If I had a .280AI(stalled build) I would carry it instead and would shoot a 175-180gr Berger around 2950fps.
Kinda cute you call your straw man "Stark"... ;)

I'd not let 20-28gr bullet weight factor in my decision.

To the OP, IMO the two you are looking at are as capable as each other regarding your desired uses. Therefore, I'd focus on getting the rifle I wanted. Some makes/models come in one, but not another.
 
Well I won’t take a condescending tone toward the wildlife biologist in the state.
I condescend to those who promulgate regulations without knowledge of the subject matter, biologists don't fall into that group as they don't do the promulgating ;)

Tissue damage destruction has much more to do with quick death than applied energy and penetration alone.
Legal - 7mm-08 - Trophy grade Nosler Accubond 140 grain at 2825- 2480 foot lbs muzzle
Illegal - 26 Nosler - Trophy grade Nosler Accubond - 140 grain at 3300- 3119 foot lbs muzzle

This is all I'm saying, hold all variables constant, bullet weight, construction, shot placement, can you really argue the 0.019 in diameter difference is more important than the 639 foot lbs of energy? Not to mention the 7mm bullet has a SD of .248, versus a .287 on the 6.5mm.

Not to mention... .30-30win, Legal. Nosler BT ammo 150grain at 2100 - 1469 foot lbs muzzle, literally less than half the energy of the 26 Nosler.

The point being we can say it’s stupid and no one has ever the denied that the 6.5 was capable in the right hands. What I can is that larger calibers tend to be more reliable killers in less capable hands to a point.

All I'm saying is that regulations don't match up to physics. Apples to apples, this is not a "capable in the right hands", literally hold everything constant, look at the numbers the rule does not make sense. Your comment makes sense if your talking 6.5 creed versus 7mm rem mag and to that regard I agree, it holds zero water per my example above.

Fish and game departments are looking at the top 5 most popular calibers and making an arbitrary cut off. Essentially they are saying you can't use a .243 to hunt elk and not really considering new 6.5 calibers.

My sample size on elk with a 6.5 caliber N= 4, not huge, but so far great results.

As always shoot the most powerful rifle you can accurately and buy high quality ammo.
 
I condescend to those who promulgate regulations without knowledge of the subject matter, biologists don't fall into that group as they don't do the promulgating ;)


Legal - 7mm-08 - Trophy grade Nosler Accubond 140 grain at 2825- 2480 foot lbs muzzle
Illegal - 26 Nosler - Trophy grade Nosler Accubond - 140 grain at 3300- 3119 foot lbs muzzle

This is all I'm saying, hold all variables constant, bullet weight, construction, shot placement, can you really argue the 0.019 in diameter difference is more important than the 639 foot lbs of energy? Not to mention the 7mm bullet has a SD of .248, versus a .287 on the 6.5mm.

Not to mention... .30-30win, Legal. Nosler BT ammo 150grain at 2100 - 1469 foot lbs muzzle, literally less than half the energy of the 26 Nosler.



All I'm saying is that regulations don't match up to physics. Apples to apples, this is not a "capable in the right hands", literally hold everything constant, look at the numbers the rule does not make sense. Your comment makes sense if your talking 6.5 creed versus 7mm rem mag and to that regard I agree, it holds zero water per my example above.

Fish and game departments are looking at the top 5 most popular calibers and making an arbitrary cut off. Essentially they are saying you can't use a .243 to hunt elk and not really considering new 6.5 calibers.

My sample size on elk with a 6.5 caliber N= 4, not huge, but so far great results.

As always shoot the most powerful rifle you can accurately and buy high quality ammo.
Though I wouldn't couch the argument in terms of energy, I think minimum caliber requirements don't take in as much experience as many would believe. Heck, in Indiana a 300 RUM with a 110gr Vmax is legal, but a 223 Rem with a 70gr Accubond is not...
 
Kinda cute you call your straw man "Stark"... ;)
I'd not let 20-28gr bullet weight factor in my decision.

To the OP, IMO the two you are looking at are as capable as each other regarding your desired uses. Therefore, I'd focus on getting the rifle I wanted. Some makes/models come in one, but not another.
It wasn’t a straw man. It was an explanation of the advantage of flat trajectories, which I threw in because so many people act like they do not matter, and because my recommendations were going to be based on the bullet weights available in the two cartridges that give the minimally flat trajectory that satisfies my personal wishes.

In terms of comparing the two cartridges in question, both are very flat shooting, and in fact improving upon them is harder than most hot rod cartridge pushers want you to know. I think the two proposed cartridges are about perfect fits for their bore diameters. In terms of hitting the target, there is very little difference between the two. In terms of killing an animal, especially with a less than perfect shot(which happens a lot more 400-500yds than at 100-300yds) the .280AI wins easily.

It’s easy to look at 28gr of lead and think very little of it, but 20% more bullet has 20% more tissue destroying potential, especially if the two bullets use essentially identical design and have essentially identical impact velocities. 20% can easily be the difference between a timely collection and a lost but wounded animal.

The only elk I’ve ever killed was with a 140Elite Hunter, and it was a less than perfect hit. He went less than fifty yards and the finishing shot was point blank while he was laying down, so yeah, it worked. More would be better. If I had the money I’d have a .280AI. I built the 6.5-257AI as an antelope gun.

Sorry Wllm1313. I don’t know why it pulled part of your post into the quote. I agree with you completely, and frankly a lot of 6.5’s smaller than the ones you mentioned will match a .270Win and with higher sectional density.
 
In the end, elk don’t read ballistics tables and it doesn’t really matter all that much. For elk to 300 yards (or even further if you’re capable) anything from a .243 to a .338 win mag will work just fine.
 
In the end, elk don’t read ballistics tables and it doesn’t really matter all that much. For elk to 300 yards (or even further if you’re capable) anything from a .243 to a .338 win mag will work just fine.
How bout a .22LR? The elk don’t read ballistics tables. The OP’s question was not “will a 6.5PRC kill elk at 500yds?” If it had been, the answer would be “yes! I’ve basically done it!(at 670yds with cartridge of similar capabilities) and if I had made a better shot, it would have worked perfectly instead of just working very well”. Instead he asked which is better and mentioned elk, so the answer is “280AI hands down”. You can launch a bullet with 20% more destructive capability without giving up muzzle velocity, or BC, and even do it while still using a bullet weight that lots of people are comfortable with. In this proposed scenario, why would anyone choose the 6.5PRC?
 
I read this entire thread and the only thing that made any sense to me was the last line off post 38 !

Where is JLS when we need him. "Dont overthink this"

just joking as you fellows are talking about things that are way out of my league.

good luck on your raft trip willm, have fun
 
How bout a .22LR? The elk don’t read ballistics tables. The OP’s question was not “will a 6.5PRC kill elk at 500yds?” If it had been, the answer would be “yes! I’ve basically done it!(at 670yds with cartridge of similar capabilities) and if I had made a better shot, it would have worked perfectly instead of just working very well”. Instead he asked which is better and mentioned elk, so the answer is “280AI hands down”. You can launch a bullet with 20% more destructive capability without giving up muzzle velocity, or BC, and even do it while still using a bullet weight that lots of people are comfortable with. In this proposed scenario, why would anyone choose the 6.5PRC?
Did I hit a nerve? You may notice I didn’t say “Use a .22, or .223, it doesn’t matter”. The fact is, most reasonable centerfire rifles (in the .243 to .338 range) will kill elk very well. The elk I’ve seen killed with a .243 died just like the elk I’ve taken with my .300 win mag. Either the 6.5 PRC or the .280 AI would be an excellent choice.
 
The OP asked question A. You quoted me and essentially said that I had incorrectly answered question B. I didn’t answer question B...question B was not asked.
I didn’t quote you in my first post. All I’m saying is there’s not really that much of a difference between the two when it comes to actually killing animals.
 
Did I hit a nerve? You may notice I didn’t say “Use a .22, or .223, it doesn’t matter”. The fact is, most reasonable centerfire rifles (in the .243 to .338 range) will kill elk very well. The elk I’ve seen killed with a .243 died just like the elk I’ve taken with my .300 win mag. Either the 6.5 PRC or the .280 AI would be an excellent choice.
There is a difference between a .243Win and a .338, and it defies physics and logic to state that there is not.
 
I didn’t quote you in my first post. All I’m saying is there’s not really that much of a difference between the two when it comes to actually killing animals.
Yeah. Error on my part. It really wasn’t a nerve.

But there is a significant difference when it comes to killing animals.
 
There is a difference between a .243Win and a .338, and it defies physics and logic to state that there is not.
I should have said “there’s not that big of a difference between the 6.5 PRC and the .280”, which is what I meant to say. Yes, there is a difference between a .243 and a .338. My point was that most reasonable centerfires will kill elk very well and that both the 6.5 PRC or the .280 would be great choices.
 
I should have said “there’s not that big of a difference between the 6.5 PRC and the .280”, which is what I meant to say. Yes, there is a difference between a .243 and a .338. My point was that most reasonable centerfires will kill elk very well and that both the 6.5 PRC or the .280 would be great choices.
20% is a substantial difference. There is a point where bigger and faster won’t make any difference any more. I don’t know exactly where that is on each different animal. I would personally argue that a 6.5PRC with a 140gr+ projectile is getting close to that point on a mule deer, but is well below that point on an elk. There is quite a bit of difference between any 6.5, and a 280AI.

The 6.5PRC will work fine. The 280AI would give me considerable comfort should something be less than perfect.
 
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