quote:

Originally posted by OTD:
these results relate to a flitching the two stage trigger, not the ammo. With consistent load and an SS109 projectile it's possible to stay with ease within 1.5 MOA (1.2MOA with GP90). There should not be a problem to place a group into the x rin of this target regardless what ammo you ar using.

I have no experience with SS109 ammo. I really have no desire to ding up my own steel targets, so if I do ever shoot SS109 it likely won't be at my practice area. So I'll have to take your word on its accuracy.

Although all my long guns are equipped with single stage triggers, I am quite familiar with two-stage triggers. IMO it's easier to flinch on a single-stage trigger than a two-stage, given that the pull that actually breaks the shot is generally quite a bit higher on a single-stage.

I do have a lot of experience with 69 SMK factory loads. Even my worst barrel groups 69s at 1" to 1-1/4" at 100 yards. Most barrels are in the .6" to 1" ballpark -- group after group after group. My best match barrel is capable of printing 69s in the .4" to .6" range. Now I can't shoot an AR-15 at 1/2 MOA on demand, but the rifle does it when my head isn't up my backside.

OK. You guys got my interest hyped up. I'll take my 550-1 out for our next shooting session. I'll exclusively shoot some surplus Swiss GP90 I got a few years back and see how it groups. My 550-1 wears a Hensoldt ZF 6X42 BL scope and I'll be shooting it off of sand bags. I'll center the scope using a laser pointer prior to taking it out.





We'll see how it groups compared to my Kimber of Oregon Model 84 chambered in .221 Remington Fireball which wears a Leupold 12X target scope. This rifle is my go to small target popper. It has no recoil, is stingy on powder, and deadly accurate out to 300 yards.

MG34_Dan, I'm really interested in comparing notes!

To say that I expected much more from this rifle, is an understatement, but I haven't had a 4x scope that has been sufficient for my eyes in over 2 decades unless shooting small pumpkins and gords count!

As mentioned previously, I've re-scoped the 550 with a 4-12x40 Leupold. Tomorrow (Friday) is my day-off, weather permitting I'll re-test ... besides, how bad could another day at the range be? Just out of curiosity, I'll take my varmint gun, and although I put it together over 15 years ago and I've lost track at the thousands of rounds through it she still shoots under an inch@100

SS109 is only the type of a projectile. US M855 ammo as an example is using the FN SS109 type projectile. There’s other manufacturers like Hirtenberger, IMBEL, PMC, MEN, Winchester etc. using the same type of projectile for their own ammo. It’s more or less a NATO standard. The P90 is slightly longer and has a different center of mass compared to the SS109.

Here is a brief report about the realistic accuracy of the SIG550. It’s based on data SIG provided to the Swiss Shooting Association for a possible new handicap rule for service rifles used in competition. It was necessary because not all generation of soldiers received the SIG550 when it was introduced. Based on the electronic test targets shot with 20’000 rilfes the average score for the PE/Stgw90 is 98.6 shot at 300m on an international CISM target with the center ring, the 10 having a diameter of 100mm (3.9”). So 98,6 means. 8 rounds went into the 10, while two left the center and hit the 9 with a diameter of 200mm (7.9”). 8 x 10 + 2 x 9 = 98 etc.). Calculated into a group size it’s about 1.5 MOA shot with GP90. The score of other ammunition is listed below. Notice the differences from manufacturer to manufacturer. The variety of scores would be worth a discussion about sub MOA results in tack drivers in general.

5.6mm GP 90 98.33
INDEP SS109 95.00
IMI Samson 94.58
China 62gr 94.17
Hirtenberger SC 93.75
SMI 62gr 93.75
PMC 62gr 93.33
FN SS109 92.92
Federal 92.92
IMBEL SS109 92.50
DAG 91.67
Winchester 91.25
Yugo SS109 90.42

What does this number tell. It basically means that everything below a score of 96 would represent only a 50% hitting probability for the 10 ring, while Federal or Winchester scores reduce probability down to 30% but is still better then some of the groups posted above which is the reason I conclude for flitching. An indicator is some of the groups sizes that would represent mentioned scores above but at 300 not 100yds.

I actually doubt that flitching was a matter of trigger weight since the SG550 comes with the mandatory 7.7 lbs trigger of the Stgw90, the lower limit for service type competition rifles in Switzerland.

What we have to understand as well is that the SIG 550 is a commercial version of a service rilfe and it’s mostly used in target competition. It’s not a competition rilfe used for military services. Comparing it with a customized AR target rifle is comparing apples with pears. Such an AR would fail the same way if it was compared in a CISM three position match against a SIGSauer 205 or a Bleikert, even the lighthearted SIGSauer Phantom standard rifle.

My experience form shooting the 550 in target shooting competition designated for Swiss Service rifles at 300m is that results in the range between 90 and 92 is good shooting while 96 and above is superior shooting and the minimum for an entry ticket in one of the serious match groups. However those who can shoot 96er scores on an average swich over to Standard rifles and compete on national level against the 150'000 match shooters who are competing each year in mandatory Swiss Army rilfe programs.


Sorry for the long post. Regards. OTD

quote:

Originally posted by OTD:
SS109 is only the type of a projectile. US M855 ammo as an example is using the FN SS109 type projectile. There’s other manufacturers like Hirtenberger, IMBEL, PMC, MEN, Winchester etc. using the same type of projectile for their own ammo. It’s more or less a NATO standard. The P90 is slightly longer and has a different center of mass compared to the SS109.

Here is a brief report about the realistic accuracy of the SIG550. It’s based on data SIG provided to the Swiss Shooting Association for a possible new handicap rule for service rifles used in competition. It was necessary because not all generation of soldiers received the SIG550 when it was introduced. Based on the electronic test targets shot with 20’000 rilfes the average score for the PE/Stgw90 is 98.6 shot at 300m on an international CISM target with the center ring, the 10 having a diameter of 100mm (3.9”). So 98,6 means. 8 rounds went into the 10, while two left the center and hit the 9 with a diameter of 200mm (7.9”). 8 x 10 + 2 x 9 = 98 etc.). Calculated into a group size it’s about 1.5 MOA shot with GP90. The score of other ammunition is listed below. Notice the differences from manufacturer to manufacturer. The variety of scores would be worth a discussion about sub MOA results in tack drivers in general.

5.6mm GP 90 98.33
INDEP SS109 95.00
IMI Samson 94.58
China 62gr 94.17
Hirtenberger SC 93.75
SMI 62gr 93.75
PMC 62gr 93.33
FN SS109 92.92
Federal 92.92
IMBEL SS109 92.50
DAG 91.67
Winchester 91.25
Yugo SS109 90.42

What does this number tell. It basically means that everything below a score of 96 would represent only a 50% hitting probability for the 10 ring, while Federal or Winchester scores reduce probability down to 30% but is still better then some of the groups posted above which is the reason I conclude for flitching. An indicator is some of the groups sizes that would represent mentioned scores above but at 300 not 100yds.

I actually doubt that flitching was a matter of trigger weight since the SG550 comes with the mandatory 7.7 lbs trigger of the Stgw90, the lower limit for service type competition rifles in Switzerland.

What we have to understand as well is that the SIG 550 is a commercial version of a service rilfe and it’s mostly used in target competition. It’s not a competition rilfe used for military services. Comparing it with a customized AR target rifle is comparing apples with pears. Such an AR would fail the same way if it was compared in a CISM three position match against a SIGSauer 205 or a Bleikert, even the lighthearted SIGSauer Phantom standard rifle.

My experience form shooting the 550 in target shooting competition designated for Swiss Service rifles at 300m is that results in the range between 90 and 92 is good shooting while 96 and above is superior shooting and the minimum for an entry ticket in one of the serious match groups. However those who can shoot 96er scores on an average swich over to Standard rifles and compete on national level against the 150'000 match shooters who are competing each year in mandatory Swiss Army rilfe programs.

Sorry for the long post. Regards. OTD

Daniel; Thank you for this information. I'm keeping a copy of it for my records.

quote:

Originally posted by kimberkid:
As mentioned previously, I've re-scoped the 550 with a 4-12x40 Leupold. Tomorrow (Friday) is my day-off, weather permitting I'll re-test ..

I'm currently working a company event -- long days, wonky hours.

Last night I briefly saw your post on the re-test. It appears to have been deleted. IIRC it stated you loaded 50 rounds of 69 SMK, showed 3 targets with probably 10 impacts each. I'm guessing the center ring was about 1" in diameter, the next ring maybe 3" in diameter. Guessing that your groups were in the 2" ballpark. I would still expect better from a 550, especially with hand loads.

You also stated that you needed to adjust the POA of the scope a bit. I recall one group being a little high, another a little right, another a little low -- did you adjust the scope as you moved from one target to the next?

I did post some new targets but after posting it and reading it I felt that the thread was starting to drift so I deleted it.

I didn't bother to re-test any of the other ammo's because it isn't ammo that I plan on shooting in this rifle ... and that's what counts.

So I just loaded up some my "plinking" ammo, its mixed headstamp but mostly Lake City; a standard CCI small rifle primer and 69 SMK (that I buy in bulk at Sierra) and Molly them myself ... as I said, this is just my plinking ammo; I didn't weigh the bullets or match the cases to a single headstamp, not even swage the primer pockets, uniform the flash holes or trim length or turn the necks ... just tumbled the brass and loaded them on my Dillon 550-B.

While I was disappointed with the first set of targets and OTD's criticism stung a bit, it made me realize that I haven't shot an actual match since Abby was born 17 years ago. Until recently wife worked an opposite shift from me and we only shared 1 day a week off together, so it made “family time” scarce and my priorities shifted ... I still get out and shoot when I can, but that's only a small fraction of range time that I had before she came along.
For instance Fritz, all the help you gave me with picking out a scope and barrel for the 6.5 Creedmoor last year, I haven't been able to shoot it yet this year. I'm hoping I can repeat the 2.5" groups at 500 yards again this fall. Plus I've got the 6.5 Creedmoor barrel from Benchmark for my SiG SSG-3000 which has only seen a few rounds through it.

Back to these targets, while this ammo isn’t match grade, I've tweaked the load to where they are better than other bulk ammo I've bought (I don’t buy match ammo, I build it myself). What this load is tailored for is an AR's with 16” barrel and 1-7 twist ... I think I’ll tweak the load a bit for the 1-10 ... I was kind of expecting these 69's to keyhole and was happy to see they didn't ... I was under the impression that with a 1-10 the heaviest bullet you would want to use is a 55.

And yes, the first set of targets I did not adjust the scope at all, I shot it right out of the case as I received it; I was just looking at how the ammo grouped, not for X's ... the set below is all the same ammo and I was adjusting for X's. The center ring is about 1" in diameter, and the 10 ring is 3" in diameter. With its reputation I do do expect better from a 550 ... I'd like to see some of MG34_Dan's results.

Anyway, these are the new targets, I've got about 15 pounds of Data 2200 to use up so and since I'm at max load for this powder and bullet weight, I'm going to try knocking down the load by one or two grains in .3 increments and see if I can tighten it up a bit, then I'll work work up some brass to get closer to match quality.



Since I've already drifted the thread, here's a couple of Abby's senior pictures. As you might imagine, she's the apple of my eye! While she has me wrapped around her finger she doesn't take advantage of it (very often) ... although she doesn't like to shoot she has taken 3 years of Martial Arts (first degree Black belt) which is what got her on the Cheer competition team ... she never wanted to take dance because they're a bunch of drama queen's ... her words.



Yes she's a varsity cheerleader, with a 3.8 GPA and has already been accepted to her collage of choice.



.

Nice shooting Tex. Make a nice graduation present. :P

For the record, I kept the grains around 60-62. Never tried anything 68 or higher.

quote:

Originally posted by Citadel:
Nice shooting Tex. Make a nice graduation present. :P

Unfortunately she's not a shooter ...

quote:

Originally posted by Citadel:
For the record, I kept the grains around 60-62. Never tried anything 68 or higher.

The first group of targets with the Hensoldt scope were for group only; 62 grain MKE, 62 grain Green tip(also known as SS109 around here) and 62 Grain Wolf Polycoat, none are Match ammo by any stretch of the imagination, it's what I had sitting around. But they were mostly stayed in the black. My 16" KAC E3 MOD1 didn't shoot that ammo any better, but it does like the ammo from the second set of targets better, but it's a 1-7 twist. Hopefully with a bit of tweaking I can tighten it up better still.

You may want to use a good copper solvent and clean the bore well in the event copper fouling is playing a role.

We have a shoot scheduled for tomorrow. Here is what I'll be shooting in my 550-1. It should be fun.:







Oh, I'll be bringing my MP5 tricked out with a "Swiss" type lower and Swiss marked flash hider. My friend's nephew will get a kick out of it. How could he not?

quote:

Originally posted by kimberkid:
Back to these targets, while this ammo isn’t match grade, I've tweaked the load to where they are better than other bulk ammo I've bought (I don’t buy match ammo, I build it myself). What this load is tailored for is an AR's with 16” barrel and 1-7 twist ... I think I’ll tweak the load a bit for the 1-10 ... I was kind of expecting these 69's to keyhole and was happy to see they didn't ... I was under the impression that with a 1-10 the heaviest bullet you would want to use is a 55.

From what I've read, the 1/10 twist will stabilize 69 grain bullets. It may be on the ragged edge of stability, so the lower the muzzle velocity, the greater the chance of wobble.

I'm not the hand loader guru, but I don't think load development is really based on twist rate. Assuming the MV is enough -- meaning that you're building supersonic loads, not subsonic ones. It's my understanding that loads are tweaked more for seating length (OAL) and barrel accuracy nodes.

I also recommend trying a commercial load for a baseline. Quality SMK 69 loads are available from Federal, Black Hills, Fiocchi, Aussie Outback/ADI, Copper Creek, Remington, Winchester, and others.

And then there's that whole nut behind the butt thingie. Probably my most finicky barrel is an LWRC 14.5" 1/7 twist piston upper. This is no match AR -- it has a 5.56 chamber and a hammer forged barrel. It shoots most 75-77 grain bullets like crap, does fine with 55 grain ball ammo, does OK-ish with 55-60 grain V-Max. But it shoots 69 SMK fairly accurately -- meaning 1" to 1.5" at 100 yards. Or so I thought. And 69 SMK by Federal, Copper Creek, and Aussie Outback/ADI. But the day we shoot, and how we're pulling the trigger than day, means a lot.

After a couple weeks on the road, I got to shoot a bit yesterday. Initial results were mediocre, then I hit a stride. Bouncing across multiple brands and weights of ammo, my LWRC finally produced nice 5-round 100 yard groups with SMK 69. Federal -- .73" and .83" and 1.26". Copper Creek -- .63" and .97". ADI -- .74" and .87". These weren't cherry picked groups, but all 7 that I shot with 69 SMK loads. From what many people would call a battle rifle, with a piston system.

I had forgotten notes which stated this LWRC produced groups in high cross winds, during the winter, with vertical variation of only 1.75" to 2.0" at 320 yard with ADI and FGMM.

Try some factory 69 grain loads. Shoot on different days. Get someone else behind the gun.

Thanks for the suggestions fritz ... I really should pick up some factory ammo, I just hate paying the price for it. Last year I did buy some Hornady 130ELD match ammo for the 6.5 Creedmoor I built and I was disappointed in it, the very first load I made for it, I took the min and max and picked the median point to start for a load and my loads, Hordady factory brass right out of the box, the same 130 bullet weight & design as the ammo I had purchased, my loads produced groups 1/2 the size as the match ammo I'd bought ... but I guess that's a base line.

You are also right that I need to get someone else behind the trigger ... I have a couple friends, the one's that mentored me when I started shooting Service Rifle matches. Now days they're retired and go mid-mornings so its hard to get to the range the same time they are ... even tho I take early and sometimes extended lunch hours! But I'll try to pique their interest with the 550
===================

MG34_Dan ... can you decipher the info on the box? Bullet weight, Muzzle velocity or ... ?
I'd really be interested in seeing your groups!

Very cool Swiss parts on the MP5 ... I've never seen such markings on the lower before, didn't even know either of those Swiss made parts existed!

quote:

Originally posted by kimberkid:
MG34_Dan ... can you decipher the info on the box? Bullet weight, Muzzle velocity or ... ?

Maybe Daniel, member OTD, can help with this as I have no clue what about this.

quote:

Originally posted by kimberkid:
Very cool Swiss parts on the MP5. I've never seen such markings on the lower before, didn't even know either of those Swiss made parts existed!

I saw this lower pictured in a Swiss Army Manual. I've also see pictures of it, but this is the only one I've ever seen in the flesh. My friend's son got it for me while he was stationed in Germany with the US Army. He found it in a gun shop while driving through Switzerland.

quote:

Originally posted by kimberkid:
MG34_Dan ... I'd really be interested in seeing your groups!

It was a very hot and humid day. The temperature was 102 degrees Fahrenheit and the mosquitoes were eating me alive. I only had 25 minutes by myself before the range filled up and everything was shot up. I was able to save three (3) of my first target. Here they are:











Like a fool, I did not bring any tools to adjust my scope's point-of-aim. I'll do that today at home in the air conditioning. No fool I!

It looks like my shots are 9cm high and 5cm right of center.

That is some great info!

I noticed that your Hensoldt manual says is for the Special Reticle however it looks very similar to my "model 1 reticle" which is 4 power.

quote:

Originally posted by MG34_Dan:

The text above the black line means: 90 (Anzahl, Nobre, Numero) rounds of rifle cartidges 90 (Gewehrpatrone 90....) written in German, French and Italian. 591-0341 ist the Swiss Army stock number. 591 means small arms ammunition, 0341 is the individual stock number for GP90 FMJ. 5.7.84T is the packaging date and the production site. July 5th,1984 T MF-Thun, now RUAT Ammotec. FS110.16B is the ammuntion lot.

@Dan, the projectile is of the old type. It's been replaced because of gas slip that wore out the barrels extensively. The new type is tombac plated. It's probably better to keep it as collectable and use the 63gr RUAG Swiss P ammo. It's GP90 in a commercial box.

@kimberkid. Dont focus too much on bullet weight. It's irrelevant. You need a projectile with the length of a GP90 projectile which is 22mm long if you want to clone the GP90 Such a projectile is somewhere in the range between 60 to 66 graind depending on material for the core and jacket used. Vo of the GP90 is 905m/s. If you want to use Swiss spec ammo follow the recommendation to Dan.

quote:

Originally posted by kimberkid:
That is some great info!
I noticed that your Hensoldt manual says is for the Special Reticle however it looks very similar to my "model 1 reticle" which is 4 power.

The scope on my 550-1 is a "Special Reticle" version. The one on my 550-2 is a "Model 1 Reticle", i.e. standard cross hair variety. Both scopes are 6X.

quote:

Originally posted by OTD:
@Dan, the projectile is of the old type. It's been replaced because of gas slip that wore out the barrels extensively. The new type is tombac plated. It's probably better to keep it as collectable and use the 63gr RUAG Swiss P ammo. It's GP90 in a commercial box.

Damn! I have over 4000 rounds of this stuff. Maybe I'll just tear some down and replace the bullets with 62gn SS109 bullets and see how that goes.

This message has been edited. Last edited by: MG34_Dan,

I think there is plenty of purists who are looking for Swiss made gold. Find 50 of them and make them happy. With 90 rounds per purist you have not done anything harmful either. Both of my 550 sent way more of this ball down the barrel without any problems. Barrel wear was mostly experienced in the competition shooter community.

But if you can, use something different. I actually provided the wrong information about the commercial GP90. It’s not RUAG Swiss P, it’s . It’s GECO made 223 Rem, 4.1g FMJ. They renamed it because “5.6mm Swiss, or real SIG550 stuff ” is not a CIP designation and it would have confused the international market. GECO belongs to RUAG ammotec and this particular ammo is made in Thun. It just drops in a differently marked bucket and is packed in a more colorful box.
I don’t know if SS109 ball would be satisfying on the long run. You have the information how it performs. An alternative would be importing a spare barrel with a 1 : 7 twist. They are about CHF 700 a piece.

Secenario three is using it. How old are you and how many round are you sending down the barrel each year? When the result of the equation is higher than 100 years it’s probably worthwhile keeping and shooting it.

MG34_Dan ... I for one would like to have a box! My email is in my profile if you're so inclined as to part with a box or three!
(I've got 3 55X's it would be appropriate to)

OTD thanks for the translation and as always, the info