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 .243 Winchester vs. .308 Winchester - Short and Long range accuracy questions.
johnsta  [Team Member]
10/18/2009 11:56:56 AM EST
Hello all.

I am somewhat new to the precision rifle game. I have a 700P with a Leupold Mark 4 LR/T scope. I am looking to buy a rifle from GA Precision and I have done a lot of reading lately on the 243 Winchester.

Does the flatter trajectory of the 243 Win make it more accurate? I have noticed that it has less drop from 100-500 yards than the 308, but after that it drops off faster than the 308 (107 to 115 grain match bullets vs the 168 and 175 grain match bullets). Does the amount of drop make a cartridge less accurate? Especially out to 1000 yards, the 308 has a flatter trajectory...or am I wrong? I have heard from many that the 243 out to 1000 is very doable. Also, I have noticed that the 243 match bullets have a better BC.

I guess what I am trying to figure out is if the 243 is more accurate than the 308 because of the trajectory.

The reason I started researching the 243 Win is because George from GA Precision said this at http://www.6mmbr.com/243Win.html,
"243 Win For Tactical Comps We asked GA Precision's George Gardner why he chose .243 Winchester for his Tactical Comp Gun. He replied, "Why would I run anything else? Think about it. I'm sending a .585 BC 115 at 3150 fps––that'll shoot inside the 6XC and .260 Rem with ease. I'm pretty sure I have found the Holy Grail of Comp Rifles. There are no brass issues like you can get forming .260 brass. I don't have to worry about doughnuts, reaming necks––none of that. And the choice in brass is great too––run Lapua if you want max reloads and great accuracy. Run Winchester if you're on a budget, and so you won't cry if you lose some cases in a match. I can get 10-round mags, and feeding is 100% reliable, since the case is identical to a .308 except for the neck. Accuracy-wise, I don't think I'm giving up anything to the .260 Rem or the 6XC." We then asked George if he'd considered using a .243 AI instead: "Yeah, the cases look cool with that 40° shoulder, but I think the standard .243 feeds a little better. And I don't think I really need the extra performance of an improved case. Run the ballistics for my load––115 moly DTAC at 3150 fps. You've got less windage than a 2950 fps 6.5-284, with cheaper brass, cheaper dies, cheaper bullets, and less recoil."


Anyways, I like the idea of a rifle that is a little cheaper to shoot/reload for with lighter recoil (not that big of a deal though). But if the 308 Win is all-around more accurate from 100 to 1000 yards, than I will stick with it.

Thanks for your replies!

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ALASKANFIRE  [Team Member]
10/18/2009 12:53:00 PM EST
Trajectory does not matter for accuracy but soemtimes a flatter shooting rifle is easier to shoot especially if you dont know the distance. It gives you a little more wiggle room.

Either caliber from GAP will shoot great. The 308 barrel will last longer if that matters to you.

I thought the 243 pretty much beat the 308 all the way out but maybe I am mistaken
glock24  [Member]
10/18/2009 1:00:27 PM EST
No, the flatter trajectory will not make the 243 more accurate, just easier to shoot because the amount of bullet drop at 1000 yards is quite a bit less. Your quote by George Garner above is one from a man who shoots a lot of tactical competitions. In that game, there is a lot of shooting at targets of unknown distance. Low recoil, flat trajectories, and cheap brass are smart decisions. He's looking for an economical solution in a game that is currently dominated by the 260 Remington and 308 Winchester.

As you may know, the 308 Winchester case has many children. It starts with a 7.62mm neck. If that same neck is reduced to 7mm, you get a 7mm-08 Remington. Reduce it to 6.5mm, and you get a 260 Remington. Reduce it once more to 6mm, and you get a 243 Winchester. With each reduction comes lighter, faster bullets with flatter trajectories, but with shorter barrel lives and less killing power.

The 243 is great for flat trajectory and a very low recoil. The 308 beats it in the payload department and with barrel life. If you're shooting paper or steel, 243 is hard to beat. If you're shooting living creatures, be ethical and choose the larger caliber.

You might also consider making less of a compromise and looking at either 260 Remington or 7mm-08. As I've mentioned, both cartridges offer flatter trajectories than the 308, but higher payloads and longer barrel lives than the 243.

If I were in your shoes, knowing what I know now, I'd opt for the 7mm-08 Remington and shoot 162 grain Hornady A-max bullets around 2750 fps from a 22" barrel. 7mm bullets have the highest BCs of any calibers we've discussed. The barrel life is almost as good as a 308, but the recoil is noticeably less. Brass is cheap and plentiful as well as reloading dies and components. And you'd be well served if you ever wanted to hunt with this rifle.

johnsta  [Team Member]
10/18/2009 1:58:51 PM EST
Originally Posted By glock24:
No, the flatter trajectory will not make the 243 more accurate, just easier to shoot because the amount of bullet drop at 1000 yards is quite a bit less.



What is the bullet drop at 1000 yards for the 175 FGMM vs the drop at 1000 with the most popular 243 match round? Anyone know?

glock24  [Member]
10/18/2009 2:05:55 PM EST
Originally Posted By johnsta:


What is the bullet drop at 1000 yards for the 175 FGMM vs the drop at 1000 with the most popular 243 match round? Anyone know?



Sorry, I'm a milliradian guy;


Drop @ 1000 meters

(308) 175g SMK @ 2650 = 13.5 mils
(308) 155g Lapua Scenar @ 2850 = 11.5 mils
(7mm-08) 162g A-Max @ 2750 = 10.2 mils
(7mm-08) 168g Berger VLD @ 2750 = 10.0 mils
(260 Remington) 142g SMK @ 2850 = 9.5 mils
(260 Remington) 140g Berger VLD @ 2850 = 9.2 mils
(243 Winchester) 107g SMK @ 3000 = 9.2 mils
(243 Winchester) 115g DTAC @ 2950 = 9.3 mils

This website is your friend.

The 175g SMK is the premier long range bullet for 308. With any of the other calibers, VLD type bullets can be used which all have the very high BCs per their respective caliber.


Rob01  [Moderator]
10/18/2009 2:30:22 PM EST
The .243 is much flatter shooting than a .308. My GAP .243 with the 115 DTAC at 2985fps takes 7.3mils or about 25 MOA. About 10 MOA flatter at 1000 than the .308 and more importantly better in the wind.

The .243 with the right bullets is an excellent round for competitions. I wouldn't shoot a .308 in matches anymore. Either a 6.5 or 6mm.

GAP builds a very accurate .243 also. Here's a 3 shot head group at 500 yards I shot at last years NorCal TBRC match


Bog_Irish  [Member]
10/18/2009 3:06:36 PM EST
Originally Posted By Rob01:
The .243 is much flatter shooting than a .308. My GAP .243 with the 115 DTAC at 2985fps takes 7.3mils or about 25 MOA. About 10 MOA flatter at 1000 than the .308 and more importantly better in the wind.

The .243 with the right bullets is an excellent round for competitions. I wouldn't shoot a .308 in matches anymore. Either a 6.5 or 6mm.

GAP builds a very accurate .243 also. Here's a 3 shot head group at 500 yards I shot at last years NorCal TBRC match
http://i23.photobucket.com/albums/b385/Rob01/norcal_tbrc08_09.jpg



That's some pretty fair shooting there, Rob!
johnsta  [Team Member]
10/18/2009 5:46:16 PM EST
Originally Posted By glock24:
Originally Posted By johnsta:


What is the bullet drop at 1000 yards for the 175 FGMM vs the drop at 1000 with the most popular 243 match round? Anyone know?



Sorry, I'm a milliradian guy;


Drop @ 1000 meters

(308) 175g SMK @ 2650 = 13.5 mils
(308) 155g Lapua Scenar @ 2850 = 11.5 mils
(7mm-08) 162g A-Max @ 2750 = 10.2 mils
(7mm-08) 168g Berger VLD @ 2750 = 10.0 mils
(260 Remington) 142g SMK @ 2850 = 9.5 mils
(260 Remington) 140g Berger VLD @ 2850 = 9.2 mils
(243 Winchester) 107g SMK @ 3000 = 9.2 mils
(243 Winchester) 115g DTAC @ 2950 = 9.3 mils

This website is your friend.

The 175g SMK is the premier long range bullet for 308. With any of the other calibers, VLD type bullets can be used which all have the very high BCs per their respective caliber.





Thank for the info! Sorry, I am kinda a Noob, what is the conversion from mils to inches?

Thanks!
glock24  [Member]
10/18/2009 5:56:05 PM EST
Originally Posted By johnsta:


Thank for the info! Sorry, I am kinda a Noob, what is the conversion from mils to inches?

Thanks!


Oh, sorry about that.

Off the top of my head, one tenth of a milliradian (0.1 mil) is 1 centimeter at 100 meters. So this would also mean one tenth of a milliradian (0.1 mil) is 10 centimeters at 1000 meters.

Take my bullet drop number in mils above and multiply by 100 to get centimeters at 1000 meters. Then take that product and divide by 2.54 to convert into inches.



johnsta  [Team Member]
10/18/2009 6:11:39 PM EST
Originally Posted By glock24:
Originally Posted By johnsta:


Thank for the info! Sorry, I am kinda a Noob, what is the conversion from mils to inches?

Thanks!


Oh, sorry about that.

Off the top of my head, one tenth of a milliradian (0.1 mil) is 1 centimeter at 100 meters. So this would also mean one tenth of a milliradian (0.1 mil) is 10 centimeters at 1000 meters.

Take my bullet drop number in mils above and multiply by 100 to get centimeters at 1000 meters. Then take that product and divide by 2.54 to convert into inches.





Thank you sir!
308Sako  [Team Member]
10/18/2009 6:22:42 PM EST
Yes, trajectory matters at unknown distances, but the real player in long range shooting is the wind. You can dial in drop these days with repeatable precision, but the wind is different for every shot you will ever fire.

Speed means less wind drift, and that is why the appeal of the light fast crowd. I totaly agree that if flesh of anytype is your target, do yourself a favor and go with the .308.
Rob01  [Moderator]
10/19/2009 1:16:01 AM EST
Originally Posted By johnsta:
Originally Posted By glock24:
Originally Posted By johnsta:


What is the bullet drop at 1000 yards for the 175 FGMM vs the drop at 1000 with the most popular 243 match round? Anyone know?



Sorry, I'm a milliradian guy;


Drop @ 1000 meters

(308) 175g SMK @ 2650 = 13.5 mils
(308) 155g Lapua Scenar @ 2850 = 11.5 mils
(7mm-08) 162g A-Max @ 2750 = 10.2 mils
(7mm-08) 168g Berger VLD @ 2750 = 10.0 mils
(260 Remington) 142g SMK @ 2850 = 9.5 mils
(260 Remington) 140g Berger VLD @ 2850 = 9.2 mils
(243 Winchester) 107g SMK @ 3000 = 9.2 mils
(243 Winchester) 115g DTAC @ 2950 = 9.3 mils

This website is your friend.

The 175g SMK is the premier long range bullet for 308. With any of the other calibers, VLD type bullets can be used which all have the very high BCs per their respective caliber.





Thank for the info! Sorry, I am kinda a Noob, what is the conversion from mils to inches?

Thanks!


Or if you just wanted to convert the mils to MOA you multiply the mil number by 3.45 which is the amount of MOA that equals 1 mil so 9.3 mils would be 32 MOA.

Also when using mils you don't have to do your ranges in meters.
CSGunWorkscom  [Dealer]
10/19/2009 3:22:31 PM EST
Originally Posted By Rob01:
The .243 is much flatter shooting than a .308. My GAP .243 with the 115 DTAC at 2985fps takes 7.3mils or about 25 MOA. About 10 MOA flatter at 1000 than the .308 and more importantly better in the wind.

The .243 with the right bullets is an excellent round for competitions. I wouldn't shoot a .308 in matches anymore. Either a 6.5 or 6mm.

GAP builds a very accurate .243 also. Here's a 3 shot head group at 500 yards I shot at last years NorCal TBRC match
http://i23.photobucket.com/albums/b385/Rob01/norcal_tbrc08_09.jpg



I have seen that be fore somewhere...


Mike @ CS TACTICAL.com
CS Gunworks is now CS TACTICAL.com
www.cstactical.com
mike@cstactical.com

Here’s some testimonials about CS GunWorks / CS Tactical
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Rob01  [Moderator]
10/19/2009 4:28:54 PM EST
I believe you saw that one in person
Combat_Jack  [Team Member]
10/20/2009 3:25:32 PM EST
IIRC a mil is 1 part height to 1000 parts distance. Easy to remember.
BSOG1  [Team Member]
10/24/2009 4:19:53 AM EST
Rob1, what kind of scope do you run ?
BSOG1  [Team Member]
10/24/2009 4:19:53 AM EST
Rob1, what kind of scope do you run ?
Rob01  [Moderator]
10/24/2009 4:28:29 AM EST
I run a Nightforce 3.5-15x50 F1 on my match rifle.
BSOG1  [Team Member]
10/24/2009 7:55:23 AM EST
i like the SN3 but the NF is priced well.
Rob01  [Moderator]
10/24/2009 8:16:47 AM EST
I like my Nightforce F1s because they have excellent glass, like mentioned they are priced well for the features they have like illuminated reticle, side parallax and matching reticle and knobs and come with rings and a sunshade. Also very important to me, they track perfectly. Only 1 of the 5 SN-3s I have had tracked. The others were way off. Needless to say I have no SN3s on my rifles.
BSOG1  [Team Member]
10/24/2009 12:45:47 PM EST
had issues with the SN3 ?did they fix it ?
Rob01  [Moderator]
10/24/2009 1:07:09 PM EST
Nope. Sent first 2 in and was told they were fixed and close enough. When I dialed on 10 mils I got around 11.3 mils of actual travel. Started going off around 1 mil which was 1.1 mil and so on. Not close enough for me. The last two I won. I checked them and they were off like the others so I sold them. I know my testing methods are correct also as I have tested 3 S&Bs, 2 Premiers and 2 NF scopes and all were right on. Hopefully they have fixed their issues but I'll stick with my NF F1.
BSOG1  [Team Member]
10/24/2009 2:16:58 PM EST
what reticle works best for range estimation ? especially with a little mirage, etc ?
i have a mst-100 and struggle a little once in a while.
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