M14 Forum

axclr8

Ok, I need a plan. I have a 18" scout squad, and a MRD for the scout rail.
I also have about 4 varieties of 155 gr bullets loaded [Nosler, Sierra new Palma, Amax, and some factory] and ready to go. I do not have access to a chrono, butI am running 47.5 gr BL-C(2) which according to the book, should give ~2800 out of a 24" bbl.
I have limited access to an indoor 50y range and limited access to an outdoor 100y range.

If this was an AR, I know the rules, for 20" zero at 25, good to 300, for 16" zero at 50 good to 250. With the M1a, I don't know the rules. Yet.

So,
#1, any one have quickload or some other method to guess about what velocity I will be pushing out of my 18" bbl?
#2, based on the above SWAG, at what distance should my close range zero be at, and where should I be hitting at 100 based on that close range zero?
#3, will my rear sight clicks even be remotely accurate?
#4, using #1 and #3 can someone help me with a SWAG range card /holdover/ comeup out to, say 500?

I realize this is ALL going to be guesswork, but I am mostly wanting to just get in the ballpark so when I do get to the range I don't have to waste alot of time experementing and taking a chance that I *wont* be on paper at 500...

bustedknuckles

great thread here, should get some great info i'll keep an eye on this one. thanks to axclr8 and to all who reply!

axclr8

Ok, well, maybe I am going to have to just wing it...

MemphisMachinists

I don't have the info you want, and forgive me if this is too elemetary.

To zero at fifty yards you don't need much. I assume you are talking irons. Set your windage at zero, and your elevation at 6-8 clicks up. If your windage is off much adjust your front site first and just fine tune it with the rear. If you are not on the paper with the first shot. Aim at the corners of the target (as far out as you can get and still be on a reference) untill you are and adjust acordingly.

I get the feeling this is not what your looking for, but someone might can use this info.

axclr8

You are right, that is rather generic info, and I understand that already. I probably did a poor job of explaining myself, so let me elaborate.

With an AR15, if you have a 20" barrel and 55gr M193 spec ammo, you zero at 25M, and you will also be zeroed at 300M. Then for everything in between, your hits will be slightly high, but always within 9". With a 14.5" M4 barrel and 62gr M855 spec ammo, you zero at 50M and are good to 250M. This is an example of the type of info I am looking for with a M1A, except I am complicating the standard BSZ assumptions with a shorter barrel and a different than standard load.

So, I have an 18" M1A which will follow slightly different rules than the standard 22" M1A, specifically, I lose velocity, and thus my bullet will drop faster than a standard rifle. I am also using slightly heavier bullets than the standard BSZ for a 22" M1A is called for.

This means the specific information I am looking for is:
#1, any one have quickload or some other method to guess about what velocity I will be pushing out of my 18" bbl?
#2, based on the above SWAG, at what distance should my close range zero be at, and where should I be hitting at 100 based on that close range zero?
#3, will my rear sight clicks even be remotely accurate?
#4, using #1 and #3 can someone help me with a SWAG range card /holdover/ comeup out to, say 500?

I realize this is ALL going to be guesswork, but I am mostly wanting to just get in the ballpark so when I do get to the range I don't have to waste alot of time experementing and taking a chance that I *wont* be on paper at 500...

In a perfect world, I would own a chronograph so I would know exactly how fast my loads are, and I would have access to a 500 yard range to verify my range card and empirically test how many clicks = what elevation for my ammo. However, I don't have either of those right now, so I am asking for a little help "doing the math" to get me in the general range. I know I can't be the first person on this site to shoot 155's out of an 18" M1A scout squad...

dragon6097

I'm famliar with the data on 5.56 and can even provide pics for said 5.56. I've not really searched for 7.62 since I'm still awaiting my build from LRB but hopefully these pics will help jog someone's memory or something.

At 50M zero out of 16"


Different zeros using 193's out of a 16"


hope this helps

MFD

Once on at 100yds, try 2moa for 200, 3moa for 300, 3moa for 400, 3moa for 500. 600 yds. go 3moa. more and that puts you a total 14moa from 100yds. Might be a bit off, but you will be on a normal target face(600yds) w/ these come ups. Add 10moa for 800,
6moa for 900 and I use 5moa for 1000yds. With your shortened barrel, loads, atmosphere, etc., the above come ups will not be exact, but you will not be far off and not be long in correcting.
Personally I don't give the wind much attention up to 300yds unless really blowing stiff, but formula I use for wind sounds complicated, but w/ practice not a problem. Range x Velocity/ 1000 = Adjustment. Range say 500yds, Velocity(wind) say 10mph coming from either 9o'clock or 3 o'clock(full value wind) will = 5000/1000 = 5moa adjustment either right or left for the wind. Well, the wind does not always blow directly from right to left or vice versa and there are other numbers to be used to determine that adjustment. One for each clock face direction, but not smart enought to remember all of those and those wind directions are hard to detect. I compormise and if seeing wind other than 9 and 3 I take half of the full value answer and put that on for the wind at that time. If wind coming from say 2 o'clock to 8 o'clock I would use 2.5moa right adjustment. Don't mean for the system to be perfect, but it has served me well for several years in shooting at longer ranges. Hope the above is of some value to you.

RAMMAC

For general numbers QuickLOAD estimates about 2650 fps.

Based on the 2650 fps velocity, QuickTARGET produced the following drop information, make sure you verify this info by actually testing it in the field.

MemphisMachinists

I figured someone would show up with this high tech stuff. At 100 yds or less you really don't need it, but notice how much velocity loss you have at 500 and 14 inches of drop. If your going to shoot at 5or6 hundred yards or more your gonna want a heavier bullet. Just out of curiosity would you post this data for a 175 gr bullet and can you vary the powder?I may have to start getting into this.
I can tell you that at 100 yds if I switch from 147gr mil surplus to 168gr handloads I gain about 2 inches in elevation.
But you have to get on the paper first.

ppcshooter1

If you zero a 20" or 16" barrel AR15 using M193 at 50 yards your bullet will cross the poa again at 200 meters, roughly 220 yards AND it will rise no higher than 3" above the poa. Plus the range numbers on the elevation wheel will actually correspond to the poi at the indicated ranges.

Marty

RAMMAC

I can run a quick version of the numbers for you but I'm not quite clear on what you want to see. Do you want a comparison between original posters 155gr bullet and a 175gr or just the data for a 175gr bullet. I assume you are wanting to compare the software numbers to some load that you are using and I'd like to do that too, it helps me refine what I need to do to get valid numbers out of the program. You asked if we could vary the powder, I'm not sure what you mean. Is there a range of powder loads that you would like to see or something specific? Are you still referring to BL-C2 or a different powder?

If you have a specific load that you want to run then the more accurate the input the more accurate the results will be. For maximum accuracy I would need;

Bullet - brand,weight, and length. At least the brand and weight. If you have them on hand and can provide the actual length of the bullet (the actual bullet, not the entire cartridge) it will make the numbers a little more accurate, if no then QuickLOAD will use the standard bullet length data this it has.

Case - brand, trim to length, and volume. At least the brand and trim to length. If you don't know the actual volume I will use the volume data that I have on hand based on the brand.

Powder - brand and how the powder charge weights you are interested in. The software will provide chamber pressure and muzzle velocity information among other things but those are the usual parameters that people are interested in.

Barrel length - just the length in inches as advertised by the manufacturer.

Temperature - temperature can have a pretty large impact with certain powders. The program defaults to 70 degrees F, if your expected shooting conditions will be no more than plus or minus 10 degrees of that then I wouldn't worry about it. Remember, hot loads built in the winter can produce very high pressures if you experience high summer temperatures.

QuickLOAD is never 100% accurate but it can be pretty close if all the data input is accurate. I usually get numbers that are within about 1% of the actual measured values that you see in the field. That usually means that if QuickLOAD predicts a muzzle velocity of 2460 fps you might see a chronograph result of about 2485 fps or so under the best of conditions. In the worst case, the velocity might be off by as much as 50 fps or about 2%. Most often I'm off by no more than 25 or 30 fps with the M1A rifle.

axclr8

Ok, so starting with the data posted above, and a bit more research, I came up with the following data card [which apparently gets REALLY mangled when you try to copy and paste]:


Velocity Bullet Wt. Bullet Wt. Bullet Wt. Bullet Wt.
2650 155 PALMA 155 AMAX 155 Nosler 147 SA
Ball Coef. Ball Coef. Ball Coef. Ball Coef.
0.504 0.435 0.45 0.401
Range Impact Impact Impact Impact
100 -0.37 -0.39 -0.38 -0.4
200 -5.5 -5.67 -5.64 -5.78
225 -7.78 -8.03 -7.97 -8.18
250 -10.48 -10.83 -10.74 -11.04
275 -13.63 -14.09 -13.97 -14.39
300 -17.22 -17.85 -17.7 -18.25
325 -21.29 -22.12 -21.91 -22.65
350 -25.86 -26.91 -26.65 -27.6
375 -30.93 -32.26 -31.94 -33.13
400 -36.54 -38.2 -37.78 -39.28
450 -49.4 -51.91 -51.29 -53.55
500 -64.65 -68.27 -67.36 -70.66
550 -82.46 -87.53 -86.26 -90.91
600 -103.03 -109.98 -108.23 -114.64

MemphisMachinists

Hope it's not steppin on the OP question , but it is relevant.
I am actually going to load some today to shoot tommorrow.
Winchester cartridge-new, never fired 2.007"
Bullet- Sierra 175 Matchking 1.255"
Powder- IMR 4895 I use a Lyman reloading manual. It says 39gr min-43.5max I normaly use the middle of these recomendations so lets go with41.5-42
Primers- I have a variety CCI 200, CCI34, CCI bench rest BR-2( I bought these back when primers were scarce and they were all I could find), Winchester WMR. Does it matter?
Barrel-22"
Temp- 40f-50f
Book says OAL 2.800, but I will be nowhere near that. Probably about 2.750or less.
600yds

RAMMAC

Your drop table makes sense, comparatively speaking. I used a 155gr Hornady A-Max when I did mine and your Palma bullet will drop less with that higher BC.

axclr8

Basically it looks like my 600Y drops are within 11 inches of SA ball, and 6 inches of each other, which is a far smaller difference than I am likely to be able to hold at 600Y with open sights, unsupported.

155 PALMA -103.03
155 AMAX -109.98
155 Nosler -108.23
147 SA -114.64


Which means, the Noslers and the Amax's for out to 400 or so and the palmas to shoot a hair flatter for the "omigoshthatsfar" targets..