7mm prc, how short is too short?

[TJ427]

Working on a 7mm PRC build and had similar question, thanks for all the great information! So much to learn about mid to long range technical details....

 

[Marty]

Federal 175 ELD-X @2800fps breaking in my 18” View attachment 705348

Nice! I'm getting 2775 FPS out of an 18" Bartlein barrel shooting the the factory Federal Premium 175 ELDXs

 

[donrleonard]

I’ve got a 16” 7PRC. It’s a 16” Bartlein. Federal Premium w/ 175gr ELD-X is @ 2680fps suppressed. Shoots ~2/3 MOA for me at both 100 and 500. The range I’m at painted their steel black and I was using holdovers, so likely will shoot a little better if I dial and have a fixed point of aim. ES was 10 for 3 shots…small sample size but I only had 1 box. Barrel has 18 rounds down it so I anticipate it’ll probably speed up 20-50fps. Shoots well enough I ordered 500 rounds.

Awesome setup. Any issue with huge muzzle flash from unburned powder, or does the can do a good job of cleaning that up.

 

[Chase723]

Awesome setup. Any issue with huge muzzle flash from unburned powder, or does the can do a good job of cleaning that up.

No issues at all. When I first decided to build it, that was one of the things I was potentially concerned about. I haven’t shot it in the dark but with the can the muzzle blast is nil. You can shoot it without ear pro under cover and you don’t get any auditory gaiting or anything. Honestly, it’s pretty dang cool…that said I wouldn’t want to shoot it without can. Lol. For perspective though, a guy was shooting a 24” braked 7PRC ~6 benches down from me and the concussion from that was intense.

 

[Chase723]

Awesome setup. Any issue with huge muzzle flash from unburned powder, or does the can do a good job of cleaning that up.

Also, I bedded the recoil lug and now it’s shooting 0.1 mil groups at 500. So, works as intended. Adequate suppression. Excellent accuracy. Super packable/portable.

 

[donrleonard]

Also, I bedded the recoil lug and now it’s shooting 0.1 mil groups at 500. So, works as intended. Adequate suppression. Excellent accuracy. Super packable/portable.

Just amazing. Sounds like a forever rifle

 

[Mattman215]

Way too short imo
May as well get a short action round with that short of a barrel. Just my .02.

 

[CMP70306]

Way too short imo
May as well get a short action round with that short of a barrel. Just my .02.

Except the long action cartridge is still faster at any barrel length which is the point.

 

[Chase723]

The only thing a short action would confer is a little weight savings. The only cartridges that come close at 16” are 7SS, 7WSM, and 7SAUM. All are great but all have to be reloaded for. This gives factory options.

 

[Mattman215]

Except the long action cartridge is still faster at any barrel length which is the point.

Thats not necessarily true.

This chart demonstrates…..

Now yes the bullet is larger out of the 7 vs the 6.5 and energy will be different wind deflection BC etc. However I think a lot of people misunderstand ballistics so was just pointing out velocities are not that much different. Plus a short action is shorter and lighter than a long action plus less felt recoil cheaper rounds and better ability to call your own shots.

Obviously build what you want but I think a 19in barrel completely ruins the entire point of the 7prc.

 

[donrleonard]

Way too short imo
May as well get a short action round with that short of a barrel. Just my .02.

Why do you say that? Seems to me they’ve got a suppressed 280AI with the length of an unbraked 308. Sounds like heaven to me.

 

[CMP70306]

Thats not necessarily true.

This chart demonstrates…..

Now yes the bullet is larger out of the 7 vs the 6.5 and energy will be different wind deflection BC etc. However I think a lot of people misunderstand ballistics so was just pointing out velocities are not that much different. Plus a short action is shorter and lighter than a long action plus less felt recoil cheaper rounds and better ability to call your own shots.

Obviously build what you want but I think a 19in barrel completely ruins the entire point of the 7prc.

I was speaking to an apples to apples comparison I.e. the 7 SAUM vs the 7 PRC or the 300 WSM vs the 300 PRC. Comparing different calibers and bullets is a completely different topic entirely as there are so many other variables to consider.

The biggest thing to me is that the larger cartridges give better performance when suppressed. For example my 18” 6.5 PRC gives the same performance as my 28” 6.5 Creedmoor yet is still 4” shorter even with the suppressor. Same with the 7 PRC, even with the shorter barrel velocity of 2664 fps per your chart that bullet will still cleanly take game in excess of 850 yards with the 1600 fps minimum.

Considering I live in PA and don’t have a place to take game over 700 yards but regularly put on deer drives through thick cover that shorter barrel works perfectly for me.

 

[Mattman215]

Why do you say that? Seems to me they’ve got a suppressed 280AI with the length of an unbraked 308. Sounds like heaven to me.

I guess different purposes and different wants. I don’t think a few inches off a barrel makes a round good or bad. For me personally I live in western states and greatly enjoy shooting 1k-2k yards every weekend as I am a short drive from that type of shooting. So for me a 19 in 7prc simply won’t work well.
When hunting out here I regularly see critters a mile or more away and often cannot close the gap much closer than 800-900 yards based on terrain.
That being said I think each person should get whatever they want based on what they want to use it for etc.
I also have a 16in custom bolt gun in 308….no it’s not a long range machine but it sure is fun.

 

[CMP70306]

I guess different purposes and different wants. I don’t think a few inches off a barrel makes a round good or bad. For me personally I live in western states and greatly enjoy shooting 1k-2k yards every weekend as I am a short drive from that type of shooting. So for me a 19 in 7prc simply won’t work well.
When hunting out here I regularly see critters a mile or more away and often cannot close the gap much closer than 800-900 yards based on terrain.
That being said I think each person should get whatever they want based on what they want to use it for etc.
I also have a 16in custom bolt gun in 308….no it’s not a long range machine but it sure is fun.

So in your case I’d probably be running a 26” barrel too. Here in the east we spend a bunch of time in and out of UTVs and trucks, climbing into box stands or tree stands and navigating through thick cover trying to push out deer. The 26” barrels with a 6” to 8” suppressor are simply too long for this kind of hunting and are more of a hinderance than a benefit.

 

[Chase723]

I had contemplated a 6.5 PRC, but already own a 6.5CM so wanted an additional legitimate step up in energy and sectional density.

 

[donrleonard]

I guess different purposes and different wants. I don’t think a few inches off a barrel makes a round good or bad. For me personally I live in western states and greatly enjoy shooting 1k-2k yards every weekend as I am a short drive from that type of shooting. So for me a 19 in 7prc simply won’t work well.
When hunting out here I regularly see critters a mile or more away and often cannot close the gap much closer than 800-900 yards based on terrain.
That being said I think each person should get whatever they want based on what they want to use it for etc.
I also have a 16in custom bolt gun in 308….no it’s not a long range machine but it sure is fun.

You talking pot shots at coyotes or big game at 900 yards? As soon as one has to start holding for Coriolis effect I’m in the 95 percent of hunters that have no business taking shots at living creatures. I would trade my 24” 7PRC for a 16” barrel any day. Unfortunately, I’ve got an XBOLT with a fluted pencil contour so I’m not sure what my prospects are for a barrel reduction.

 

[Mattman215]

You talking pot shots at coyotes or big game at 900 yards? As soon as one has to start holding for Coriolis effect I’m in the 95 percent of hunters that have no business taking shots at living creatures. I would trade my 24” 7PRC for a 16” barrel any day. Unfortunately, I’ve got an XBOLT with a fluted pencil contour so I’m not sure what my prospects are for a barrel reduction.

I have shot 3 deer at 981 and 997 and 860, and one bear at 990. Coyotes not so much never can get them to stop running and screwing around. 1k is prob my max limit on living animals and conditions need to be right. I have passed on a bull elk and a bear that were at 1100, I felt it was too far and the envelope of a quick humane kill was too narrow.

 

[ACHILLES]

Way too short imo
May as well get a short action round with that short of a barrel. Just my .02.

To short for what, your personal criteria? You never asked what ranges he’s hunting. No factory short action round can push a 175gr at 2680fps in a 16” bbl.

Thats not necessarily true.

This chart demonstrates…..

Now yes the bullet is larger out of the 7 vs the 6.5 and energy will be different wind deflection BC etc. However I think a lot of people misunderstand ballistics so was just pointing out velocities are not that much different. Plus a short action is shorter and lighter than a long action plus less felt recoil cheaper rounds and better ability to call your own shots.

Obviously build what you want but I think a 19in barrel completely ruins the entire point of the 7prc.

Irrelevant your comparing different cartridges and calibers

I guess different purposes and different wants. I don’t think a few inches off a barrel makes a round good or bad. For me personally I live in western states and greatly enjoy shooting 1k-2k yards every weekend as I am a short drive from that type of shooting. So for me a 19 in 7prc simply won’t work well.
When hunting out here I regularly see critters a mile or more away and often cannot close the gap much closer than 800-900 yards based on terrain.
That being said I think each person should get whatever they want based on what they want to use it for etc.
I also have a 16in custom bolt gun in 308….no it’s not a long range machine but it sure is fun.

Just because someone’s else barrel length doesn’t fit your personal needs or hunting style doesn’t mean it’s to short. Back before I ran suppressors my stuff was 26-30”. So I don’t blame you for getting all the velocity you can. But the 175s at 2680 don’t drop below 1800fps until after 900yards.

7prc 16”
Federal ammo 175s 2680fps at 3000DA
1801fps at 900yards

7prc 24”
Federal ammo 175s 2985fps at 3000DA
1820fps at 1150yards

 

[Mattman215]

To short for what, your personal criteria? You never asked what ranges he’s hunting. No factory short action round can push a 175gr at 2680fps in a 16” bbl.

Irrelevant your comparing different cartridges and calibers

Just because someone’s else barrel length doesn’t fit your personal needs or hunting style doesn’t mean it’s to short. Back before I ran suppressors my stuff was 26-30”. So I don’t blame you for getting all the velocity you can. But the 175s at 2680 don’t drop below 1800fps until after 900yards.

7prc 16”
Federal ammo 175s 2680fps at 3000DA
1801fps at 900yards

7prc 24”
Federal ammo 175s 2985fps at 3000DA
1820fps at 1150yards

Someone’s feelings got hurt

He went on a public forum asking for opinions, so I gave my opinion. I only run suppressors as well.

 

[ACHILLES]

Not at all, we’re all having a discussion. I stated my opinion to with an apples to apples ballistic comparison.