Considering downsizing to 6 cm from 7 PRC

[Tanner]

I'd look at the 6.5 PRC with a good suppressor. I absolutely hate recoil. I'm pushing 156 Bergers at about 3k under max charge with a 24" can. Smoked my buck at 750 yards this year.

Usually always about to see my hits as long as I don't get crazy with my zoom.

Not down playing the 6 creed, I want one. But that's a pretty big step down in energy.

The 6.5 is pretty awesome. A joy to shoot and hammers game. My kids shoot mine without an issue. Ha it does rock my 7 year old a little off the tripod but when you only weigh 60-70lb

That’s a good call. Would also save the OP from swapping bolts, mags, etc.

Recoil management seems to be the biggest issue in this circumstance.

 

[ARK_Ginger]

Could you tell me what you are showing with the gel blocks?

What he’s showing is a bit disingenuous and is common in the industry where terminal ballistics is poorly understood or they just want to make a marketing statement. The pressure wave that makes the block jump and makes cool slow motion pictures has not been scientifically shown to decrease incapacitation times.

 

[Mountain_Life]

@satchamo did you check your zero when you got home? Still waiting to hear an update. I appreciate the thread.

 

[Weldor]

Last year we did three open Shoot2Hunt with 34 students firing just over 40,000 rounds. The vast majority of shooters were “very” experienced shooters and hunters and all but 2-3 stated that they had a on demand killing range of 600 plus yards when they showed up. Cartridges ranged from 223 to 300 RUM’s, and most everything in between, with several well assembled and very accurate 7 PRC’s with 180gr ELD-M’s and large 6.5 magnums with 147gr ELD-M’s.

In pretesting in mountainous terrain that the students had never shot in or seen, on life size steel big animal targets painted naturally, and with all the scenarios and shots being recreations of actual shots from hunting the year prior- from just under 100 yards to 1,106 yards.
About a third of the targets people ran out of time before getting a shot off. Of the ones that were fired, first round hit rate in vitals from 100 to 427 yards was about 20%, and when including hits to the legs/guts/antlers about less than 40%. Of the target beyond 427 yards to 1,106 yards, first round hit rates were less than 10%, with most were being pure luck by the shooters own admission.
The performance of the cartridge and bullet had no correlation with hit rates with three exceptions- sub 427 yards, 223’s got almost all of the first round hits. Past 427 yards, the 22 creedmoor was the only one that stood out, and mainly from 2-3 shooters that used it. @Dioni A did well comparatively with using a 6.5 PRC. Out of 28 shooters, the only one to get a first round hit on the elks vitals at 1,106 yards was from a 223 with 77gr TMK (though she had been through a partial course two years prior).

If you looked at a graph showing the amount of scenarios that the shooters got a shot off at all, the first round hits rates, and especially the second round corrections on wounded animals- 22cals and Dioni shooting his 6.5 PRC dominated. As recoil/rifle movement went up, success went down. Interestingly, even though Dioni shot his 6.5 PRC well in the course, he used a 22CM exclusively this year for hunting instead, and I believe he stated in part because of what he saw happening in the course he attended.


Removing myself, the two shooters with the highest hit rates on pretest (again never having seen or shot the targets or in that place at all) were the other two main teachers. Both using 308 winchesters, and 3-9x’ish MOA scopes- both were about 80% first round hit rate in vitals out to 700 yards.


Note:

During the course while training, and the last day of again shooting novel shots in the field that the shooters have never shot or seen before- out to 500 to 600 yards the hit rate was nearly identical between 223’s and 7 PRC’s- including 1st round vital hits which averaged over 70% in very high winds. Again, the 22 cm showed to have the best performance from 400-1,200 yards, with two (IIRC) shooters using 6 CM’s and doing about the same (that is over 80% first round hits out to 800 plus yards) as the 22cm users.


Most of the responses from people at the end was that it doesn’t really matter what the cartridge/bullet’s external ballistics within reason is up to about 500 yards- either you can call the wind well enough, or you can’t; there isn’t much difference when shooting side by side in realistic scenarios. Past 500 yards, fast 22’s and 6mm’s ruled. All/nearly all, stated that they would trade the ballistic performance advantage of the big magnums for the shootability and absolute ability to watch the rounds hit of the smaller cartridges.

Thanks, Great info.

 

[Dioni A]

Just wanted to clarify an earlier comment. When I said, I think the 22 Creedmoor or six Creedmoor are perfect. Theyre still a little bit boutique and hard to get. A 243 Winchester is basically identical to 6 creed. A 22-250 is almost identical to a 22 creed. It’s really easy to get hung up on what’s cool and new when there’s tons of stuff out there that nearly duplicates the performance and is more available. Your skill matters infinitely more than the difference in modern cartridges on a ballistic chart.

 

[mtnbound]

Transference of energy and the difference between wound channel expansion with large and small bullets, which is key to internal organ disruption during the impact cycle

Ok, but the provided gel blocks are not comparable data. The pictures are not taken at the same point in time. One has the temporary would cavity and the other does not. You also are not clear if the impact velocity is the same and if the bullets are also of the same design and manufacturer. How is using incomparable data validating your statement?

 

[huntnful]

This a .223 with 75gr. BTHP


And a 300 PRC with 225 ELDM



I’m not sure of the impact velocities, but Hornady’s website has lot of good calibrated gel testing. Very cool to look at.

Rifle Ammunition - Hornady Law Enforcement

“Ten bullets through one hole,” was the philosophy of J.W. Hornady, the company’s founder. This great idea of accuracy and perfection has continued from the first bullet made more than half a century ago, right through today.

www.hornadyle.com

Click on the actual bullet name that you’re interested in, and it’ll bring you to a new page. Scroll down and you’ll see “ballistics” and “gelatin”. Select gelatin to see all the testing for that bullet.

 

[Article 4]

Ok, but the provided gel blocks are not comparable data. The pictures are not taken at the same point in time. One has the temporary would cavity and the other does not. You also are not clear if the impact velocity is the same and if the bullets are also of the same design and manufacturer. How is using incomparable data validating your statement?

Man you are reaching for anything to discredit what is a fact.

Energy transference in rifle bullet is an undeniable fact. Period.

Gel is well recognized as the best like comparator without using actual animals or humans as guinea pigs.

The penetration of a rifle bullet into a block of ballistic gelatin is experimentally and computationally studied for enhancing our understanding of the damage caused to human/animal soft tissues. The gelatin is modeled as an isotropic and homogeneous elastic-plastic linearly strain-hardening material that obeys a polynomial equation of state. Effects of numerical uncertainties on penetration characteristics are found by repeating simulations with minute variations in the impact speed and the angle of attack. The temporary cavity formed in the gelatin and seen in pictures taken by two high speed cameras is found to compare well with the computed one. The computed time histories of the hydrostatic pressure at points situated 60 mm above the line of impact are found to have "two peaks", one due to the bullet impact

So tell me how your opinion trumps the science and explain how they aren’t comparable?

How do you know they weren’t taken at the same point in time?

Explain to me how one is temporary and the other isn’t?

Impact velocities and bullet size between a 6 and 7mm would rarely be the same. why would someone want them to be in the field? defeats the purpose of having bigger bullets moving just as fast. Which is the WHOLE-point!!

 

[Dioni A]

This a .223 with 75gr. BTHP
View attachment 806741

And a 300 PRC with 225 ELDM
View attachment 806747


I’m not sure of the impact velocities, but Hornady’s website has lot of good calibrated gel testing. Very cool to look at.

The law enforcement site? I don’t think you can access this from the regular site

 

[huntnful]

The law enforcement site? I don’t think you can access this from the regular site

Sure you can. Click on it lol

 

[huntnful]

Seems like Hornady agree with us. Go figure lol.

Yes a bigger bullet, of the same style, makes a bigger wound. But the pictures you shared weren’t a legit comparison. One was just penciled through a gel block to make it seem worse than it is.

These are apples to apples. Same test, under the same conditions. .223 makes a hell of a wound.

 

[Article 4]

Yes a bigger bullet, of the same style, makes a bigger wound. But the pictures you shared weren’t a legit comparison. One was just penciled through a gel block to make it seem worse than it is.

These are apples to apples. Same test, under the same conditions. .223 makes a hell of a wound.

Glad you agree.

My point is and was, that a larger bullet moving at similar speed is transferring more energy has MORE affect than a small bullet. The bullet difference is on purpose.

 

[Article 4]

What he’s showing is a bit disingenuous and is common in the industry where terminal ballistics is poorly understood or they just want to make a marketing statement. The pressure wave that makes the block jump and makes cool slow motion pictures has not been scientifically shown to decrease incapacitation times.

Your last sentence is at least correct. Although you use a double negative to say it, perhaps a freudian slip, what science agrees with. Kinetic energy KE = 0.5 • m • v2, expanding rounds can cause extensive damage, such as pulverizing bones, tearing blood vessels, and liquefying organs.

Try it yourself

Bullet Energy Calculator

Find out how much energy a bullet fired from a weapon carries using this bullet energy calculator.

www.omnicalculator.com

 

[roadrunner]

I don’t think so if you are responding 3 pages later

What makes you think he read everything? Post showed up when it did...

 

[Formidilosus]

Glad you agree.

My point is and was, that a larger bullet transferring more energy has MORE affect than a small bullet. The bullet difference is on purpose.

No, your “point” was disingenuous and misleading at best, if not outright dishonesty. By your response to being questioned about it, the latter is most probable. And, neat that you used AI to form a response.

The difference between a heavy for caliber 6mm ELD-M and a heavy for caliber 30cal ELD-M in the temporary stretch cavity when impacting at the same velocity is about 1” to 1.5”. That is 6”+ for the 6mm and 7” to 7.5” for the 30cal.

 

[Article 4]

Last year we did three open Shoot2Hunt with 34 students firing just over 40,000 rounds. The vast majority of shooters were “very” experienced shooters and hunters and all but 2-3 stated that they had a on demand killing range of 600 plus yards when they showed up. Cartridges ranged from 223 to 300 RUM’s, and most everything in between, with several well assembled and very accurate 7 PRC’s with 180gr ELD-M’s and large 6.5 magnums with 147gr ELD-M’s.

In pretesting in mountainous terrain that the students had never shot in or seen, on life size steel big animal targets painted naturally, and with all the scenarios and shots being recreations of actual shots from hunting the year prior- from just under 100 yards to 1,106 yards.
About a third of the targets people ran out of time before getting a shot off. Of the ones that were fired, first round hit rate in vitals from 100 to 427 yards was about 20%, and when including hits to the legs/guts/antlers about less than 40%. Of the target beyond 427 yards to 1,106 yards, first round hit rates were less than 10%, with most were being pure luck by the shooters own admission.
The performance of the cartridge and bullet had no correlation with hit rates with three exceptions- sub 427 yards, 223’s got almost all of the first round hits. Past 427 yards, the 22 creedmoor was the only one that stood out, and mainly from 2-3 shooters that used it. @Dioni A did well comparatively with using a 6.5 PRC. Out of 28 shooters, the only one to get a first round hit on the elks vitals at 1,106 yards was from a 223 with 77gr TMK (though she had been through a partial course two years prior).

If you looked at a graph showing the amount of scenarios that the shooters got a shot off at all, the first round hits rates, and especially the second round corrections on wounded animals- 22cals and Dioni shooting his 6.5 PRC dominated. As recoil/rifle movement went up, success went down. Interestingly, even though Dioni shot his 6.5 PRC well in the course, he used a 22CM exclusively this year for hunting instead, and I believe he stated in part because of what he saw happening in the course he attended.


Removing myself, the two shooters with the highest hit rates on pretest (again never having seen or shot the targets or in that place at all) were the other two main teachers. Both using 308 winchesters, and 3-9x’ish MOA scopes- both were about 80% first round hit rate in vitals out to 700 yards.


Note:

During the course while training, and the last day of again shooting novel shots in the field that the shooters have never shot or seen before- out to 500 to 600 yards the hit rate was nearly identical between 223’s and 7 PRC’s- including 1st round vital hits which averaged over 70% in very high winds. Again, the 22 cm showed to have the best performance from 400-1,200 yards, with two (IIRC) shooters using 6 CM’s and doing about the same (that is over 80% first round hits out to 800 plus yards) as the 22cm users.


Most of the responses from people at the end was that it doesn’t really matter what the cartridge/bullet’s external ballistics within reason is up to about 500 yards- either you can call the wind well enough, or you can’t; there isn’t much difference when shooting side by side in realistic scenarios. Past 500 yards, fast 22’s and 6mm’s ruled. All/nearly all, stated that they would trade the ballistic performance advantage of the big magnums for the shootability and absolute ability to watch the rounds hit of the smaller cartridges.

Thanks for sharing this. On the whole, informative for sure. A few questions...not challenging you at all, just love testing and want to ask some clarifying questions to be sure I understand.

If the performance of the cartridge had nothing to do with the hit rates, as you stated, can we assume from 3 longer range hits, were the hits a result of the smaller cartridges or was it the shooters themself? If you pull the 3 instructors out, you and the two others, what were the results from the 31 shooters in total actual hits at any distance? Was there any significant data split on smaller to larger calibers?

A 308 is larger than a 22 creedmoor, do you feel like that is not a good comparator, and less about the caliber - the instructors seemed to hit with 308, making it appear it was more the shooter than caliber.

Do you feel like if you had a chance to run a test where each shooter brought two rifles, perhaps a 6mm something and a 7 or 30mm something, it would show anything maybe differently?

Of the targets beyond 427 yards to 1,106 yards, first round hit rates were less than 10%, with most were being pure luck by the shooters own admission. That is 2-3 hits out of 34. Don't care what caliber they are shooting, that would not work in the field period.

Any chance you all plan to follow up on this test and maybe do something bigger?

 

[Article 4]

No, your “point” was disingenuous and misleading at best, if not outright dishonesty. By your response to being questioned about it, the latter is most probable. And, neat that you used AI to form a response.

The difference between a heavy for caliber 6mm ELD-M and a heavy for caliber 30cal ELD-M in the temporary stretch cavity when impacting at the same velocity is about 1” to 1.5”. That is 6”+ for the 6mm and 7” to 7.5” for the 30cal.

So the 30 caliber cavity is bigger - thanks for supporting my point. I am happy to have a data based and scientific discourse, I take no issue with being questioned with factual support -vs- opinion - can you send me a link to the data you quoted?

@Formidilosus - you are a bully and reprehensible in the way you attempt to intimidate people (me) with your offensive attitude. So I am a liar, let's debate this completely F2F sometime, and lets see if you can prove what the data and I have shown is the truth.

 

[Formidilosus]

So the 30 caliber cavity is bigger - thanks for supporting my point.

@Formidilosus - you are a bully and I take offense to you calling me a liar. Happy to debate this completely F2F sometime if you are available.

Did you or did you not purposely show pictures of a smaller caliber and a larger caliber impacting at widely different impact velocities to skew the belief that there is a massive difference between the calibers, with no information letting the reader know that you did so?

Take offense all you want- providing purposely misleading information is in fact “dishonest”.

 

[Article 4]

Did you or did you not purposely show pictures of a smaller caliber and a larger caliber impacting at widely different impact velocities to skew the belief that there is a massive difference between the calibers, with no information letting the reader know that you did so?

Take offense all you want- providing purposely misleading information is in fact “dishonest”.

Yes, I did purposefully show that - and if you read the thread, you would have found out why.

 

[Article 4]

Did you or did you not purposely show pictures of a smaller caliber and a larger caliber impacting at widely different impact velocities to skew the belief that there is a massive difference between the calibers, with no information letting the reader know that you did so?

Take offense all you want- providing purposely misleading information is in fact “dishonest”.

So let me ask you, are you so delusionally slanted that you think that a 108 grain berger flying at 3000 fps will have more penetration, more energy transfer, and more total killing ability than a 215 grain berger flying at 3000 fps?