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9/22/2017 12:11:25 AM
Posted: 10/28/2003 9:02:08 AM EDT
I got an Oly 16" SUM upper a while back and mounted it to my Colt H-Bar Match lower. It already has a good triger. Took several trips to the range to break in the barrel. Lot's of cleaning!

Now I have shot probably 12 different loads for groups and have narrowed down my choice striclty by accuracy to Black Hills 55g Vmax and 55g soft point. Nothing else I have shot even comes close. FMJ ammo shoots 3 - 4" at best.

This is with a good mount and a good scope with a good bench rest. Is this the best I can expect? I don't handload so I can't go that route. I have some handloads I had made for my 20" Hbar, and that shoots .3" in that rifle, but I am hesitant to shoot it much in this 16" configuration.

I have this set up with a standard A2 stock, BUIS sights (it was HELL finding a mount to clear that ARMS #40)to use as a ranch rifle during deer season. I will head shoot does and shoot any small game opportunity allows.

I was lead to believe after much research that this SUM was capable of sub MOA accuracy. I have not found that to be the case.

Can anyone tell me if I am getting what I should and if not, any ideas how to squeeze out some better accuracy?

Link Posted: 10/28/2003 9:12:13 AM EDT
[Last Edit: 10/28/2003 9:13:03 AM EDT by Ghost-Shooter]
Sorry if this sounds stupid, but you are shooting .223 ammo, not 5.56, right? The SUM barrels are cut to the minimum SAAMI .223 Remington chamber, so a 5.56 round in it might be detrimental. Also, what kind of groups are you getting with the BH ammo? I don't shoot precision much, so I don't know of any other ammo to try. Hopefully, one of the more experienced match shooters will chime in. Ghost
Link Posted: 10/28/2003 9:35:09 AM EDT
As Ghost Shooter mentioned, make sure you are shooting .223 and not 5.56. The Oly chambers are minimum SAAMI, read that as a tight .223 I have a 20" SUM that really didn't start to shoot until after around 300 rds. You may want to take up handloading or have someone load to your specs. My best recipe is LC brass, 27gr of H335, and Fed 205 primer pushing a 40gr Vmax MOLY bullet. OAL at 2.60", the mag won't allow any longer cartridge. This rifle hasn't seen anything but molys, so I can't speak for everyone. It will, however, shoot a .765" group at 200yds. My best improvement came from a JP fire control pkg, it is sweet. Baby that barrel, but don't overclean. Clean from the chamber out, you don't want to mess up that broach cut rifling. Keep trying, it will straighten out.
Link Posted: 10/28/2003 10:59:34 AM EDT
Hey Ghost - that is not stupid at all, I appreciate the input. Yes I am shooting ONLY .223 ammo. The BH groups have ranged from 4" (69g match) to the 1" groups with the 55g loads mentioned previously. I honestly had not thought about the barrel 'shooting in'. I have had that happen before and just didn't think of it. I broke it in right and don't shoot more than a couple hundred rounds before cleaning. I'm kind of anal about clean equipment. I clean only from the breech with a chamber guide and coated rod. At the range, I use only a bore snake for quick between load clean ups. The barrel has also just been treated with Moly Fusion so it cleans up really easily now. Thanks again for the advice.
Link Posted: 10/29/2003 3:02:45 PM EDT
Well, I was at my range one day with my first batch of econo 55gr FMJ handloads, and when I started complaining about 2" groups, all the old timers laughed and made fun of me hehehe. Though you might do better than 3-4" with FMJ, the fact is that it's never gonna be as accurate as match grade or more expensive non FMJ ammo, really. Also, my own experience...my Armalite upper does 1/2 to 3/4 moa all day with a 55gr Nosler BT...but that same load only gave my 1" or a little more through the 16" rifle I tried it through. I worked up a load for the 16" rifle...4895 and 69gr Sierra Match Kings...that gave me 4 sub moa 5 shot groups (I made 20 rounds of 3 different charges). I'm getting close to the sweet spot, but a shortage of $$ has curtailed my load workup for a while. BTW, how did the VMAX ammo shoot? What kind of accuracy did you get out of that. I wouldn't worry about going to a heavier bullet, or even a lighter one...try some 52 or 53s through it. You're gonna have to experiment a little, but you should have no trouble going sub moa with that rifle, from what I hear about it.
Link Posted: 10/29/2003 3:27:37 PM EDT
[Last Edit: 10/29/2003 3:30:39 PM EDT by mark5pt56]
Some barrels are finicky. I had a 20"SUM 1n10" that would shoot a .8" average at 100 yds (eight, five shot groups) with PMC 55gr ball(red/white box) The best I got from it was .6" (same standard)with both PMC Silver line using the 69gr SMK's and my loads(25gr IMR 4320, 69 SMK's Federal case) A couple of those were .4". M193 was around 1" and it hated M855-2-2 1/2", terrible. Double check the mountings and take your time with the fundementals! I would be happy if you can consistently stay under an inch. Depending on what you are doing with the rifle. Know what it is capable of in a controlled environment, then shoot from different positions to see what you can do with it. Mark
Link Posted: 10/29/2003 5:51:27 PM EDT
You might try Hornady TAP (if it's still available), or Federal Gold Medal Match. You never can tell your rifle may like it. If your going to shoot alot, I'd seriously look into getting set up for reloading. You can roll better ammo, and save money too.
Link Posted: 10/30/2003 6:58:35 AM EDT
Thanks guys, all good stuff. My 16" hated the Hornady and PMC... they were both 3-4". I do get a lot of looks at the range too... it is rather a black rifle, you know. And this is deer season, so every wahoo with a $1500 .338 Weatherby (to shoot 100 deer mind you) that plunks down 1" groups frown on black guns. I don't really pay them any attention. I can shoot rings around most of them with the Hbar. I guess I will just have to keep trying. I am going to use this to hunt with so Match loads would be a last choice - it hasn't shot any 69g load well yet and if I DO find one that is just all that, I can probably use it. I head shoot does and whatever other vermin I stumble across. Fenian - I don't rememberf off the top of my head what the Vmax did, but it wasn't great. I will get back with a report after this weekend... I'm going back to the drawing board... er.. shooting bench.
Link Posted: 10/30/2003 10:37:33 AM EDT
I also have a 16" SUM barreled rifle with 1-in-8 twist. It now has about 600 rounds through it and the accuracy has been consistant since round #1. It is topped with a Leupold 4.4 -14 scope and has a JP Fire Control system Using a variety of experimental handloads, my 100yd 5 shot groups are never worse than 1.25 MOA. The best has been 0.5 MOA using moly-coated Sierra 52 gr HPBT Match bullets and Hodgdon BLC-2 powder. The worst groups were with Hornady 55gr V-Max ahead of Varget powder. After many loads through about a dozen AR's there is no doubt that the AR barrels can be [b]very finicky[/b] to changes in reloading components. Once you find your best load stick with it unless you are like me and continually experiment. Good Luck. Do give your barrel some time to settle-in.
Link Posted: 10/30/2003 10:58:37 AM EDT
[Last Edit: 10/30/2003 10:59:54 AM EDT by JTR8541]
Markbo, This might be another stupid question, but are you also using a copper solvent like [I]Shooters Choice[/I] to remove the copper left in the bore. I found this to be an issue with my DPMS Bull rifle. The first 100 rounds took forever as I was trying to keep track of how well the rifle was shooting. I was using [I]Shooters Choice[/I] copper solvent about every five rounds for about the first 50 then about every ten rounds for the next 50. The rifle probably didn’t need 100 rounds to be broken in but it shoots extremely well now. Best regards, J
Link Posted: 10/30/2003 11:33:22 AM EDT
Thanks RUss & Jt. Going back Sunday to work out the last two or three best loads I have. I broke this barrel in using the one shot, clean repeat process. Not even 3 rounds. Did this for 100 shots. Next 100 shots did the 3 shots, clean & repeat. I use Shooter's choice for solvent then Sweet's for copper fouling. I also recently treated the bore with Moly Fusion. It makes it a LOT easier to clean! Before I would have to use 2 wet patches, scrub, dry patches 6 to 8 times to get it perfect. Now I use one wet patch and 2 dry ones twice and I am done... and I could clean my eyeglasses with that last patch... it is spotless. I am very tedious about a clean gun and I know for a fact this one is not fouled with powder or copper residue. Until I breakdown and start reloading, I guess I will have to hope that one of the 3 Black Hills loads I have narrowed it down to can remain sub MOA. Thank goodness they are the blue box and not the red!
Link Posted: 10/30/2003 12:43:12 PM EDT
I'm pretty much sold on using moly coated bullets all the time. Cleaning is really easy with no visible copper jacket fouling. I rarely even use a bore brush. A couple of wet patches followed by 6 dry patches results in a clean bore. I have even left the bore wet with Sweet's for 6 hours then run a dry patch and got no green copper residue. Another nice benefit of moly is I can usually "push" my loads another .2 to .5 grains without any noticeable pressure signs. This will provide another 75 to 250 fps velocity depending on the load.
Link Posted: 10/30/2003 1:11:39 PM EDT
Russ, I am not talking about Molybednum bullet coating. Moly FUsion is entirely different. I actually was turned on to this stuff at rimfirecentral.com. Go to this website and check it out yourself: http://www.shootersolutions.com/ There is some talk about groups being more consistent... not improving accuracy per se, but more groups being more consistent (which I have definitely found to be the case in my 10/22. I have not shot the AR enough to see the result, though cleaning is an absolute breeze.
Link Posted: 10/30/2003 2:37:10 PM EDT
No you don;t.I have a 16"oly and the best result's i have had are with winny 55 sp superX.Those thing's rock,plus the wally world 40 hp,both give me realy tight group's at 100.Thewinny sp give me 2"group's at 300.This is of course when i am haveing a GOOD day at the range.Of course there are day's when the dammed thing plain refuse's to shoot straight.
Link Posted: 11/4/2003 11:23:59 AM EDT
OK, a little update. I got the ammo all figured out. I have ordered 1/2 case each of the Black Hills blue box (reloads in 50g VMax and 55g SP. The red box (new ammo) 55g SP shot sub MOA as did the 52g HP match, but the red is too expensive and I don't have much practical use for the match ammo. Now here is the funny part: Since my previous trip to the range, I treated the gun with Moly Fusion (see link above). All the loads were more consistent, i.e. there were no fliers and the group sizes were always just about the same without much variation. All of these 52-55g loads still only shot about 7/8" groups - but they did so every time. The Vmax and the SP unfortunately shot to a different POI so I can't interchange them, but once sighted in for one load, I can live with it. 7/8" is not what I was hoping to get out of this upper - especially after talking to the guys at Olympic. They were adamant that I should expect 1/2" groups with the right ammo. But I got what I got and that is what I will tell everyone when I see the 'what's the best upper' posts that are sure to come. Thanks for all your input guys. If I find anything else out new or different I will post it here.
Link Posted: 11/4/2003 2:26:21 PM EDT
I think the standard is to hold a 4" MOA at 100 yards or better. You can do better then that but it depends allot on the shooter and the load. Practice makes perfect or ok you improve but don't get to bent out of shape on it.
Link Posted: 11/4/2003 3:09:46 PM EDT
Sounds to me that you have done more than your share to get accuracy. Now I'd say since the barrel was new, it is time for them to provide you a barrel exchange that gives what they claim. Bad barrels come along just like cars and lemens. Jack
Link Posted: 11/4/2003 5:40:36 PM EDT
Markbo- Your original post stated you had a "good" scope and this was to be a deer rifle.My carbine that I hunt with will shoot 1/2" w/ several loads when mounted to a 10X scope. But, my "good" scope for hunting has a heavy duplex and 4X (max), and the same loads in the same upper won't stay under 1". The "good" deer hunting scope making the difference. Just thought I'd mention this!
Link Posted: 11/5/2003 4:30:49 AM EDT
Originally Posted By berdan: Markbo- Your original post stated you had a "good" scope and this was to be a deer rifle.My carbine that I hunt with will shoot 1/2" w/ several loads when mounted to a 10X scope. But, my "good" scope for hunting has a heavy duplex and 4X (max), and the same loads in the same upper won't stay under 1". The "good" deer hunting scope making the difference. Just thought I'd mention this!
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Good point. When shooting my SUM at lower power magnification (6x) my groups will tend to open up. Not the scopes fault, just that the low power will not let you center on the target as well as a higher power. I shoot a 6.5-20x, so if you get the opportunity try another scope.
Link Posted: 11/5/2003 5:04:24 AM EDT
Originally Posted By Markbo: I got an Oly 16" SUM upper a while back I was lead to believe after much research that this SUM was capable of sub MOA accuracy. I have not found that to be the case.
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The Ultramatch rifle is the one with the claims to .25MOA. What twist is the barrel? The 1X10" may not like your heavier bullets. If you're not happy with the accuracy send the upper back. OAI has a great warranty.
Link Posted: 11/5/2003 6:17:54 AM EDT
Thanks a bunch for the input guys. GIJohnny: I personally would not own a rifle that would only shoot 4" at 100 yards. I have pistols that will shoot that good. Berdan & MartinTN: The 'good scope' is an Aetec3.5-10 power. It is extremely clear and I can see the 1 1/2" white bull split 4 ways by the thin genter crosshairs. I could mount a 6-20X that I have just for grins, but I honestly doubt it would improve much. But hey... I guess it's worth a shot! 3rdtk & Tweak: You know, I had not thought of returning this unit for a replacement. I did LOT of research and soul searching before making this decision and you know... you are right. I should not settle for OK accuracy when I paid for excellent accuracy. It is a 1:10" twist and it should shoot lighter bullets best. Oly said that would be in the 49-55g rainge and that is what it is shooting best, so I am not suprised... that is what I wanted. And just for clarification... it is NOT a primary deer gun, though I will head shoot a couple of does. But I will slap that 20 power scope on there this weekend just to eliminate that as a variable and if groups are not tighter, I will contact OLY straight away. Thanks again guys! Mark
Link Posted: 11/5/2003 6:41:29 AM EDT
My 16" Oly will shoot .78" with Winchester 45gr. varmint ammo.
Link Posted: 11/6/2003 9:45:45 AM EDT
Little update. I left work early yesterday and hit the range. Mounted a different - 20X scope on it. Groups did not improve. Quite the opposite in fact. They were slightly larger. Weird, huh? But I contacted Oly by Email, told them abut the problem and they responded immediately - just reutrn it and we will take a look. I am sending it back by UPS tomorrow along with my scope mount, just so they can eliminate that as a problem. I'll post back with news when I know something.
Link Posted: 11/6/2003 10:44:37 AM EDT
Originally Posted By Markbo: They were slightly larger. Weird, huh?
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Not really, scopes only allow you to miss more accurately. [:D]
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