Does your primary extraction work properly ? I've done a lot of 6 Creedmoor barrels none have been sticky on extraction
6mm Creedmoor and .243 WIN, is there really a difference?
- Thread starter welder179
- Start date
Does your primary extraction work properly ? I've done a lot of 6 Creedmoor barrels none have been sticky on extraction
Wow, there's a lot of misinformation in this thread... read above with both patience and caution.
I'll touch on shoulder angles between 243 and 6 CM for example.
1) Difference applies to throat erosion. The soft shoulder angle of the 243 bounces the flow into the throat area of the barrel on the opposing side. Conversely, the steep shoulder angle of the 6CM bounces the flow into the brass neck on the opposing side. This sacrifices the expendable brass and helps to protect the throat of the barrel.
2) The cases will grow in length more with the 243 after each firing due to the soft shoulder angle than the 6CM. The sharp shoulder angle helps reduce that forward flow of brass, so cases will not need to be trimmed as aggressively or as frequently.
3) The sharp shoulder angles of the 6CM help generate a certain level of turbulence that translates to more consistent powder burn and more consistent muzzle velocities.
So ya... the 6CM 6x47 Lapua, 6BR, 6 Dasher etc all share these common traits which is just a little better than cartridges of old.
Not to say that I'm a big fan of the 6CM, because I'm not. The 6.5CM is close to ideal, but the 6CM is too hot. Barrel life is questionable with a 6x47 Lapua… so why would you want even less barrel life with a 6CM?
I've always believed that the powder charge of the most favored long range rounds hold about 1/3 of the bullet weight used for long range shooting. 223=80/3=26.6 gr, 6mm =115/3=38.3 gr, 6.5=140/3=46.7 gr 308=185/3 = 61.7 or even 220/3=73.3 gr... that's where the real long range performance will be found with a good balance of all things.
I'll touch on shoulder angles between 243 and 6 CM for example.
1) Difference applies to throat erosion. The soft shoulder angle of the 243 bounces the flow into the throat area of the barrel on the opposing side. Conversely, the steep shoulder angle of the 6CM bounces the flow into the brass neck on the opposing side. This sacrifices the expendable brass and helps to protect the throat of the barrel.
2) The cases will grow in length more with the 243 after each firing due to the soft shoulder angle than the 6CM. The sharp shoulder angle helps reduce that forward flow of brass, so cases will not need to be trimmed as aggressively or as frequently.
3) The sharp shoulder angles of the 6CM help generate a certain level of turbulence that translates to more consistent powder burn and more consistent muzzle velocities.
So ya... the 6CM 6x47 Lapua, 6BR, 6 Dasher etc all share these common traits which is just a little better than cartridges of old.
Not to say that I'm a big fan of the 6CM, because I'm not. The 6.5CM is close to ideal, but the 6CM is too hot. Barrel life is questionable with a 6x47 Lapua… so why would you want even less barrel life with a 6CM?
I've always believed that the powder charge of the most favored long range rounds hold about 1/3 of the bullet weight used for long range shooting. 223=80/3=26.6 gr, 6mm =115/3=38.3 gr, 6.5=140/3=46.7 gr 308=185/3 = 61.7 or even 220/3=73.3 gr... that's where the real long range performance will be found with a good balance of all things.
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There is NO DIFFERENCE between the two cartridges. It is simply marketing something new.
Two rifles built to the same specs and quality using 8T custom barrels, ACCURACY will be the same using handloads.
No difference
Two rifles built to the same specs and quality using 8T custom barrels, ACCURACY will be the same using handloads.
No difference
There is no accuracy difference, not something statistically significant at least, but to say there is no difference between the cartridge is wrong.
This is like the 260 rem compared to the 6.5 Creed fight that I swear happened 2 weeks ago.
The Creeds will do what the .243/.260 will do with less power, less case prep work, and longer barrel life. Are they big differences, no, but they are differences.
It’s interesting to see how traditionalism plays out in the assumptions made with respect to each cartridge.
One cartridge is traditionally offered with a slow twist barrel, so the cartridge is no good for long range shooting, but put the same chamber in a fast twist barrel and suddenly the lights come on.
Companies spit out 6 and 6.5 CMs with 1:8 barrel twist rates, sell cartridges with heavy bullets and guys brag em up like no tomorrow, but that old 243 is just no good. (nobody seems to notice the barrel twist for 80 grainers)
Even assumptions about the humble 223 Rem is no good for long range… well not in the SAMMI spec offering 2.25 OAL regardless of twist rate you wont get enough speed to be effective at 800 yards, but throat it to OAL 2.6 and run 80 grain SMKs with 25 grains of Varget and all of a sudden it shoots side by side with a 308.
Actually the 223 runs a little better than 308 if you run it within PRS rules when we consider achievable velocity within bullet weight limitations.
One cartridge is traditionally offered with a slow twist barrel, so the cartridge is no good for long range shooting, but put the same chamber in a fast twist barrel and suddenly the lights come on.
Companies spit out 6 and 6.5 CMs with 1:8 barrel twist rates, sell cartridges with heavy bullets and guys brag em up like no tomorrow, but that old 243 is just no good. (nobody seems to notice the barrel twist for 80 grainers)
Even assumptions about the humble 223 Rem is no good for long range… well not in the SAMMI spec offering 2.25 OAL regardless of twist rate you wont get enough speed to be effective at 800 yards, but throat it to OAL 2.6 and run 80 grain SMKs with 25 grains of Varget and all of a sudden it shoots side by side with a 308.
Actually the 223 runs a little better than 308 if you run it within PRS rules when we consider achievable velocity within bullet weight limitations.
FWIW I love the 243 win, one of my fav calibers all time. But walked into my local shop a few weeks ago and he had "Used" (NIB) savage 10T-SR in 6 creed sitting there. 26" 8 twist. The price was right so decided to give it a shot and see what all the hype was about. After picking up 107gr SMK's, and some 108gr ELD-M factory ammo I went home sighted it in with factory, 3 shots covered with a nickle at 100. And then loaded up these 107's with H4350. With very minimal load development I was able to achieve that magic 1 hole load at 200, and launching these 107's at 3105 with a ES of 5. This load is also nowhere near hot, I know I could run em faster but I havent even tried and unsure if accuracy would suffer or not.
My buddy is also a hardcore 243 fan and was astonished when I showed him the data and how easy it was to find a load. Im shooting 87gr V-max's for coyotes at 3475 avg FPS with H4350 as well, and also shooting 0.32 MOA at 200 yards. This is with cheap hornady brass, and very minimal effort into finding a load for it. He was shooting 87gr V-maxes outta his 243 at 3300 with more powder, same barrel length but 9 twist instead of 8 and accuracy was nowhere near the 0.32 MOA
After shootin a 243 win for as long as ive been around rifles, I do believe the 6CM has the edge over a 243. The steeper angle of the shoulder increases barrel life on the 6CM, I will say I think it is also a more accurate round, and very forgiving to load for. Even mine shot well under 3/4 MOA in just about every load I tried but I was chasing that 1 hole load and found it quite easy. I will never knock a 243, Ive shot a lot of animals with one, and still to this day have a few that I enjoy shooting, but I do the 6CM having the edge over it as far efficiency is concerned.
My buddy is also a hardcore 243 fan and was astonished when I showed him the data and how easy it was to find a load. Im shooting 87gr V-max's for coyotes at 3475 avg FPS with H4350 as well, and also shooting 0.32 MOA at 200 yards. This is with cheap hornady brass, and very minimal effort into finding a load for it. He was shooting 87gr V-maxes outta his 243 at 3300 with more powder, same barrel length but 9 twist instead of 8 and accuracy was nowhere near the 0.32 MOA
After shootin a 243 win for as long as ive been around rifles, I do believe the 6CM has the edge over a 243. The steeper angle of the shoulder increases barrel life on the 6CM, I will say I think it is also a more accurate round, and very forgiving to load for. Even mine shot well under 3/4 MOA in just about every load I tried but I was chasing that 1 hole load and found it quite easy. I will never knock a 243, Ive shot a lot of animals with one, and still to this day have a few that I enjoy shooting, but I do the 6CM having the edge over it as far efficiency is concerned.
It seems like we are getting the same old arguments over the 6CM that we have seen regarding the 6.5 CM. I am sure that we will see more of the same about the 6.5 PRC just as I did when I talked about my 6.5 - 300 RCM/6.5 EXTREME, back in 2010, long before the PRC was even thought about. My 20 EXTREME wildcat has gotten me a lot of hateful comments from a few individuals who refuse to believe what I say about it and the 270 PHC that I am working on has already been targeted by some of these individuals. This excerpt from the gundigest, see linkhttps://gundigest.com/gear-ammo/ammunition/6-5-prc-extending-riflemans-reach, does a good job of describing these people. Many consumers and wannabe gun experts only think new cartridges are a means for manufacturers to sell more guns and more ammo. About the same number of shooters are also so emotionally attached to a certain cartridge that they cannot accept — nor will they acknowledge — something better has come along.
And, too, there’s this thing called neophobia, which is an extreme or irrational fear or dislike of anything new, novel or unfamiliar. For all of these reasons, some shooters are completely ignoring or bashing the 6.5 PRC.
The article features the 6.5 PRC and mentions the 6.5 CM but the reasons for new cartridges being developed are the same for the 6 CM and some well designed wildcats. It is not because the old cartridges were terrible but rather because they were not designed to run with the modern long range bullets and manufacturers are bound by their Saami Specifications so they are not commercially viable in todays market.
And, too, there’s this thing called neophobia, which is an extreme or irrational fear or dislike of anything new, novel or unfamiliar. For all of these reasons, some shooters are completely ignoring or bashing the 6.5 PRC.
The article features the 6.5 PRC and mentions the 6.5 CM but the reasons for new cartridges being developed are the same for the 6 CM and some well designed wildcats. It is not because the old cartridges were terrible but rather because they were not designed to run with the modern long range bullets and manufacturers are bound by their Saami Specifications so they are not commercially viable in todays market.
Know that should be a sticky! Nicely said!
BenchrestJohn
CGN Regular
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- Maple Ridge, BC
Is a soft po*rn healthy for men's prostate?
BenchrestJohn
CGN Regular
- Location
- Maple Ridge, BC
Its a cartridge for millennials. 30 years old grown bearded men who cry about recoil and masterbate about bullet length.
= danrifleman762
CGN Ultra frequent flyer
- Location
- Southern Alberta
6mm Super LR is where it's at. A 243 case with the shoulder pushed back for a longer neck and 30° shoulder. The shoulder to case wall transition stays in the same spot but the shoulder to neck transition gets pushed back.
(If we're talking about miniscule differences in cartridge performance.)
(If we're talking about miniscule differences in cartridge performance.)
I once met a shooter at a benchrest competition and he said he cannot understand why members keep whinging about throat burning cartridges,
It’s like taking the hottest cheerleader out for a date and having amazing ### afterwards and then complaining it cost too much...
He has a point you know
It’s like taking the hottest cheerleader out for a date and having amazing ### afterwards and then complaining it cost too much...
He has a point you know
These threads sure go full retard pretty fast... in rifles with the same twist and same barrel length shooting the same bullet, performance will be incredibly close. The advantage of the Creedmoor case is the same for 6mm as it is for 6.5mm, it's shorter length allows you to run heavy for caliber (and hence long) bullets without them being pushed back into the case while still fitting in a mag. Same as with .260 vs 6.5 Creedmoor. This has led to it being a much more prevalent chambering in rifles optimized for log range shooting than the .243. This boomer vs millennial #### is retarded.
I've come to learn that CGN is not a place to have intelligent, pragmatic and objective discussions about anything related to precision rifle shooting.
But I agree with you, the advantage to the 6 creedmoor is that its OAL is optimized for mag feeding, which can be a big deal depending on what you are doing. Other then that, they are damn near ballistically identical.
