Long Range - Hit Probability Analysis

[TimeWillTell]

.5 MOA 6mm - 105 - 2950 - 47% Hit - 9.9Lbs. of RECOIL
View attachment 6888176

.5 MOA 6.5mm - 147 - 2750 - 68% Hit - 13.58Lbs. of RECOIL
View attachment 6888182


.5 MOA 7mm - 180 - 2550 - 69% Hit - 15.94 Lbs. of RECOIL
View attachment 6888180

Yeah I don't think anyone will disagree a heavier bullet at long range has a higher probability. It's a balance that 7mm would be viable in a OK (where I live) comp that stretches out a ways. But a 6.5 might be the best compromise still in that scenario. I'm not recoil sensitive but since I started shooting positional stuff more recently I've started to understand why people do 6mm.

 

[cheapmoa]

Yeah I don't think anyone will disagree a heavier bullet at long range has a higher probability. It's a balance that 7mm would be viable in a OK (where I live) comp that stretches out a ways. But a 6.5 might be the best compromise still in that scenario. I'm not recoil sensitive but since I started shooting positional stuff more recently I've started to understand why people do 6mm.

I understand. I was doing this to see the big picture not for PRS. I think for me a 7mm SAUM that I could use with 2600 FPS Loads up to 3100FPS loads would just be a great all around setup. I am not a PRS shooter so it was nice to get feedback from everyone.

 

[morganlamprecht]

I understand. I was doing this to see the big picture not for PRS. I think for me a 7mm SAUM that I could use with 2600 FPS Loads up to 3100FPS loads would just be a great all around setup. I am not a PRS shooter so it was nice to get feedback from everyone.

i think a 7 saum is an awesome all around caliber than can be configured to run well in many scenarios...run light and fast for smaller game, load it heavy for long stuff or big animals, still has great ballistics without stupid amounts of recoil...short mags are sexy

 

[TimeWillTell]

I understand. I was doing this to see the big picture not for PRS. I think for me a 7mm SAUM that I could use with 2600 FPS Loads up to 3100FPS loads would just be a great all around setup. I am not a PRS shooter so it was nice to get feedback from everyone.

Yeah I think it's a great choice! Down loading to 2600 may reduce the consistency a but with a light case fill but def should fine a good medium load for all around then can hot rod if needed for like elk or something.

 

[TripleBull]

Have you run the numbers on 375 Lethal Magnum? Specs are 3500fps @ 350 grain and 3200 fps @ 400 grain (Cutting Edge, but not sure which the AB crew are running, probably something different than below)

 

[BlackFenix]

Thanks for putting this effort in! It is a really great read. I wish Coldbore was out on more devices.

 

[Rthur]

I understand. I was doing this to see the big picture not for PRS. I think for me a 7mm SAUM that I could use with 2600 FPS Loads up to 3100FPS loads would just be a great all around setup. I am not a PRS shooter so it was nice to get feedback from everyone.

7 saum does a lot well inside 1200 for case capacity/caliber.

R

 

[cheapmoa]

7 saum does a lot well inside 1200 for case capacity/caliber.

R

7 SAUM seams to have the most well rounded use profile. What other cartridges are like the SAUM? The brass is not bad on price either.

 

[cheapmoa]

Have you run the numbers on 375 Lethal Magnum? Specs are 3500fps @ 350 grain and 3200 fps @ 400 grain (Cutting Edge, but not sure which the AB crew are running, probably something different than below)

View attachment 6888615

View attachment 6888616

1200 YARDS
375 Lethal - 352 MTAC - 3500 - 71%
375 Lethal - 402 MTAC - 3200 - 68%

 

[Rthur]

7 SAUM seams to have the most well rounded use profile. What other cartridges are like the SAUM? The brass is not bad on price either.

7wsm, 7-300 wsm, .284, .284AI, .284 Shehane and many more.
Depends on if you'd want to run a wildcat.

R

 

[cheapmoa]

7wsm, 7-300 wsm, .284, .284AI, .284 Shehane and many more.
Depends on if you'd want to run a wildcat.

R

What would you recommend for 180 ELDMs?

I will be loading mag length in a short action.

 

[Rthur]

What would you recommend for 180 ELDMs?

I will be loading mag length in a short action.

For out to 1200 I'd go 162 eld-m/saum and with the right reamer you would be around 2.950 COAL or under.
I'll push it over 3k without running it very warm on load.
Accurate mag has a wsm/saum mag that will hold 7 for this.
The 180 is better served in a action that can handle a COAL 3.100 and mag as well.
Surgeon used to make a "medium" action as I've built one for a friend. FB was .188 on that reamer.
The 180 can be ran in a sa but case capacity is lost.

R

 

[TimeWillTell]

For out to 1200 I'd go 162 eld-m/saum and with the right reamer you would be around 2.950 COAL or under.
I'll push it over 3k without running it very warm on load.
Accurate mag has a wsm/saum mag that will hold 7 for this.
The 180 is better served in a action that can handle a COAL 3.100 and mag as well.
Surgeon used to make a "medium" action as I've built one for a friend. FB was .188 on that reamer.
The 180 can be ran in a sa but case capacity is lost.

R

Defiance has a rebel XM and a BDL bottom metal that gives length up to 3.2". I'm thinking this would be excellent for a 7 saum with 180. Maybe even 195? Maybe not able to push that hard enough. Hunting build that is since no detach mag.

 

[Sheldon N]

Brass cost/availability along with sizing die options is your biggest factor in picking one of the 7's. The SAUM is cheapest/most available but the WSM's and WSM derivatives will give you more case capacity.

While it's better to have the bullet seated clear of the neck/shoulder junction that's not really possible in a mag fed short action. They will shoot fine with the bullet down in the case too. I shot a 7 SAUM mag fed with Berger 195's. The bullet was darn near sitting on the primer but it shot fine, lol.

RL-26 powder is your friend.

 

[Rthur]

Defiance has a rebel XM and a BDL bottom metal that gives length up to 3.2". I'm thinking this would be excellent for a 7 saum with 180. Maybe even 195? Maybe not able to push that hard enough. Hunting build that is since no detach mag.

Forgot about the rebel xm.
Do they have a dbm for this action?

R

 

[TimeWillTell]

Forgot about the rebel xm.
Do they have a dbm for this action?

R

Yes but only the BDL floor plate style (obvious I guess since no mags at that length). Perfect in my mind for a hunting rig.

ETA you could probably also use a wyatts box

 

[derek1s]

Ive been curious about the new Sierra 200g .30 cal bullets. How does a .300wsm, 200g (.712) and 2900fps & 3000fps print?

 

[Old Dude]

So basically it looks like what would be a 7/300 shooting 180 ELD-M at 3300 gives you the best hit chance, but the most recoil.

.this is what I'm looking at I have a 300WM now and when the barrel goes I want to switch it to this. I have the brass so why give it up and start all over

 

[jaybigboy34]

Could you do 225 eldm's going 3005fps with an accuracy of .5 moa?

thank you

 

[Lynn Jr]

I think it's pretty clear that pushing the highest BC bullet at the highest velocity will help you as the distance is increased.
BUT
In Benchrest accuracy is all that matters for 5 or 10 shots.
In F-Class you will be shooting 20 shot strings so the ultra hotrod cause too much heat and the recoil is double to 4 times that of a group match
I don't shoot PRS matches but from what I see you have a velocity limit to protect the steel?
That would count out those hotrod as well.
In the testing the group size was set as 1 moa which any cartridge can do.
The advantage you see with the 6mm cartridges is it's all but impossible to get a 6BR or 6 Dasher to shoot that bad even with horrible reloads by a rookie.
On the other hand the 375/50 at 3800 FPS would be shooting good at 3/4 moa or triple the group's size of a Dasher.

 

[338LMAI]

I just bumped into this thread and given the work and time everyone's put in here I'm a little reluctant to ask--but can't help myself: How about a 338 LMAI using Flatline 256s at 3400 with a .5 moa? These are coming out of a gain twist 1:9.5-1:8 32" barrel and the stated G7 is .434.

Thank you and what an interesting read!

 

[Diver160651]

Skipping I am sure this has been said:

1- SD of 15 is so bad it kills every thing - nobody should be shooting ELRvwith such bad SDs.

2. Your velocitis are over optimistic on some and relatively low on some others— ie 2900 for 168 Berger’s in a 7mag. I was running 3125.. my standard 338 ran one hole groups with the flatlines at 3015 with only a 26 inch barrels.

3. There is no substitute for mass. ELR is a bit of a game if missing and quick corrections 6.5 and 7mm are MUCH harder to spot than a heavy 30 or 338. Do you will get more hits all else being equal with the 338 or heavier 30 is you can self pinpoint the poi immediately.

4. Some of the magnum cartridges are much easier to achieve lower SDs with full cases of slow burning powder.

Just adding real world stuff - that said it may have been said already- edited to add, I see Lynn basically said much of the same.

 

[jasent]

Skipping I am sure this has been said:

1- SD of 15 is so bad it kills every thing - nobody should be shooting ELRvwith such bad SDs.

2. Your velocitis are over optimistic on some and relatively low on some others— ie 2900 for 168 Berger’s in a 7mag. I was running 3125.. my standard 338 ran one hole groups with the flatlines at 3015 with only a 26 inch barrels.

3. There is no substitute for mass. ELR is a bit of a game if missing and quick corrections 6.5 and 7mm are MUCH harder to spot than a heavy 30 or 338. Do you will get more hits all else being equal with the 338 or heavier 30 is you can self pinpoint the poi immediately.

4. Some of the magnum cartridges are much easier to achieve lower SDs with full cases of slow burning powder.

Just adding real world stuff - that said it may have been said already- edited to add, I see Lynn basically said much of the same.

Agree 100%. This seems geared toward prs and less towards ELR