IMPORTANT REQUEST

[IdahoWoodsbummer]

I have an important request. I am in a remote part of the sandbox right now and need some data badly. I cannot go into very many details for OPSEC and PERSEC reasons. I am doing a contracting job.

Here is the scoop. My coworkers are not able to get onto a range longer than 25 meters and I do not have my Sierra ballistics program with me. resupply is not an immediate option.

I need some folks on the board to crunch some numbers for me. THIS MUST BE DONE ACCURATELY AND EXACTLY. THIS IS CRITICAL.This will take a little doing too.

Two sets of data for the same ammo.

Ammo is military M118 which I believe has a 173 grain bullet. Not sure on maker but it looks just like a sierra MK.

Two rifles.
#1 SR25 with a 20" BBL. This is a gas operated gun so 20" bolt gun data will not work. Bore to center of scope is approximately 2.5"s

#2 M24 with a 24" tube. Bore to center of scope is approx 1.5"s

I need to get the velocities for this ammo. Then someone to put in data. Here are the factors. Sea level. 100 yard zero. Temp data for 90, 110,120,140 degrees. Need it rigged in MOA's, not inches of drop, such as 500 yard = 6.65 moa,700 yards = 8.2 moa etc. out to 1000 yards.

This is a bit of an off the wall request but I figure who to best get the data from than a bunch of LR nuts /ubbthreads/images/graemlins/smile.gif.

I will post some pics in a few months when I return on break.

Thanks in advance for the help.

CARLOCK ARE YOU GETTING THIS????

 

[Shawn Carlock]

Bummer,

I'm on it. Get real velocities ASAP and I'll fine tune the charts. Until then I'll get the best velocity numbers I can. If you are able, email me direct and let me know where to email it back to. Keep your head low.

 

[Buffalobob]

m-24



10th SFGA--B'bob's old home


special delivery


Ask IdahoWB if it says "Lake City" arsenal on the box. Maybe it doesn't say that anymore.

 

[Buffalobob]

P.S.

I'm retired and got nothing in particular to do until September. Send me a plane ticket and I 'll be happy to come help out for a while.

 

[Meister]

if it's hp it sounds like M118LR, it is a SMK in 175g. if it's a ball round it's m118sb and is 173g. Unfortunately lots can differ greatly in velocity. Shawn is the man, he'll get you fixed up.

 

[Shawn Carlock]

Bummer,

Assuming you are smart enough to tell the difference between a hollow point and ball ammo? The looks like a matchking is infact a 175 SMK. I have all figures based on your info and a relative humidity of 20%. What is this crap of scope height of <u>approximately</u> 1.5 and 2.5 inches? Might you possibly measure them ( comparing them to your unit does not count ). Let me know where to send your info. Keep low and don't become a bullet sponge.

 

[4ked Horn]

Something to get you started.
These drops in inches are straight out of "Ultimate sniper" By major John L. Plaster. Regarding M-118, 7.62mm NATO Match boat-tail Ball 173 Gr.

I assume these numbers are for a military issue bolt gun and will hopefully help until Shawn comes up with something better. The conditions for this data are unknown.

Yards
100 - Zero
200 - -3" or 1.5 MOA
300 - -13.5" or 4.5 MOA
400 - -32" or 8 MOA
500 - -60" or 12 MOA
600 - -99" or 16.5 MOA
700 - -150" or 20.5 MOA
800 - -212" or 25.5 MOA
900 - -293" or 31.5 MOA
1000- -395" or 38 MOA

Sorry that is all the info I had that was relevant.

Good luck.

 

[Bart B]

[ QUOTE ]
These drops in inches are straight out of "Ultimate sniper" By major John L. Plaster. Regarding M-118, 7.62mm NATO Match boat-tail Ball 173 Gr.

[/ QUOTE ]I know these numbers aren't right. Having worn out 4 barrels in 7.62mm NATO converted M1 Garands and a lot of the ammo was LC M118 Match (M2 173-gr. bullet), my zeros (I've always remembered them) were as follows at sea level for the M1NM rear sight having a bit more than 1 MOA per elevation click; one can calculate the bullet drop at each range from this data:

200 yards, 5 clicks up from the bottom (front post height changed to do this; 200 yard drop = 10 inches).
300 yards, 3 up from 200 yards, up 8 total.
600 yards, 12 up from 300 yards, up 20 total.
800 yards, 10 up from 600 yards, up 30 total.
900 yards, 6 up from 800 yards, up 36 total.
1000 yards, 7 up from 900 yards, up 43 total (that's about 440 inches of drop).

I'll run my Sierra Bullets software and see what happens for their 30 caliber 175-gr. HPMK.

 

[abinok]

Plasters book data is just flat BAD!!!! I wonder sometimes if it was done intentionally. Bart, were those comeups from a 20"gasgun?
A friend's Knight SR25Mk11 does 2544fps with the 175gr, and its 63fps faster with the supressor mounted. We have found that his drop data come very close to the standard Leupold cam for 168gr ammo from 24" barrels. You may want to give that a try. Shawn probably has access to far more stuff than me, so i he has a different average velocities for more than 1 rifle, please disregaurd my info.

 

[4ked Horn]

[ QUOTE ]
Plasters book data is just flat BAD

[/ QUOTE ]
Sorry, Didn't know. /ubbthreads/images/graemlins/blush.gif

 

[IdahoWoodsbummer]

I should have mentioned. This is NOT M118LR which is a 175gr MK. It is M118, It is Lake City.It has a very tiny hollow tip but is classified as ball, I just found the data, it is 173 grain
If someone has a gas gun ar10 or sr25 with that ammo it would be great to get actual velocities.

Thanks everyone for the help. I do not trust the "sniper" boards as much for data.

Carlock, I saw super Dave in Jordan on my way through. He is living large.

Y'all save some rockchucks for me /ubbthreads/images/graemlins/grin.gif

Idaho.

 

[abinok]

4ked,
Once upon a time I lived and breathed the technical data in that book... then I started putting one and one together... read through the mildot data a few times and something funny strikes... He makes no mention of the differances between army and marines mildot reticles, and uses the math indescriminately too!!!!
And the list goes on and on...
Now my plaster book is full of notes in the margins on what is wrong /ubbthreads/images/graemlins/smile.gif

 

[Shawn Carlock]

Bummer,

I have all of your data. Just let me know where to send it. I shot a 20" DPMS with the LC M118 yesterday. Average velocity 2558 fps, also shot some through a 24" custom Rem 700 that belonged to a local customer average velocity 2624 fps. The bullet you talk about is the 173 version and after some reserch I find the BC is just .004 less than the SMK. I have all the data you need I just need a location to send it to. There is to much to post here. I also included 10 mph wind and 1 mph moving target lead.

About Plaster - My understanding from some of the been there, destroyed it and got the ribbon guys I know of the Plaster / Vietnam era, is that Plaster was a good SOG guy but never spend any amount of time as a sniper he just collected info and wrote the book. I was not there but have gotten this same story from a number of people I really trust.

 

[Bart B]

[ QUOTE ]
Bart, were those comeups from a 20"gas gun?

[/ QUOTE ]No; standard 24-inch 7.62 NATO Garand barrel with 1:12 twist (I know, .30-06 ones had 1:10 twist but these were made to US Navy specs). They were custom made by Springfield Armory, MA but were tight; .2995" bore, .3076" groove, broach rifled and extremely uniform dimensions from throat to muzzle. They shot the same M118 ammo about 75 fps faster than the normal, larger bore &amp; groove diameters standard service barrels had. With good handloads, the best of them would stay inside 4 inches at 600 yards; not too shabby for a gas gun's ability to have all those moving parts (op rod and all) back into battery exactly the same for each shot - and a whippy barrel to boot!

That's gonna be the big error factor in what this guy wants. Without chronographing ammo from the acutal barrels, the muzzle velocity I use with the software may be 50 fps or more off from what they get. To say nothing of the powder temperature when the round's fired causing velocity changes. And different lots have different muzzle velocities. Whatever I come up with will be a SWAP; Scientific Wild *** Prediction.