quote:

Originally posted by MG34_Dan:
<snip>
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.

After seeing this, I took another look at my scope and realized its nothing like what I have for my HK91 ... I'm starting to think its may be a 6 power instead of at 4 ... I need to look around and see if I can find a PDF but I did snap a couple pictures of it ... and borrowed one that Citidel took of the reticle to see if maybe you or ODT could share any info about what I actually have as I don't have any info on it.

It’s a conventional Hendsoldt 4x24 Model 1 scope of the first type from the late 60’s early 70’s with the common FINABEL mil rad reticle. (FINABEL is an early NATO standard). Uncommon is the .223 BDC. The more common is the Bundeswehr version with the 7.62 BDC. the LH dial is for site adjustment, the RH dial is for focus adjustments. The elevation dial is graduated in 100m increments and “should” compensate .223 ball. Handling is similar to the Fero Z24.

The provenance of this scope is raising some quesitons. Is the scope aftermarket or did it come originally in a factory set with the rifle, case and accessories?

According to Citadel it did, he said he had loaned the owners manual out and would try to get it back and send it but made no promises ... not sure if it would have any provenance in it or not ... it would be nice to have such things but ...

Sorry, i dont question your competence.

I’m looking at the scope and some of its markings don’t into my limited world. It does not mean there's something wrong. Therefor the question.

No offense taken, I was looking for information! This mount & scope, could be something the original department specified when they ordered the rifles or as an afterthought for the individual once it was assigned, it is odd that it’s an old design since this rifle was just ordered in the 90’s ... I just wish they had gotten a 6x like MG34_Dan’s!

I’m tempted to use a set of NATO rings I have to mount the Leupold on the mount it came with (instead of the BT) until I come up with more “mad money” to get a higher power European model scope and possibly complete scope & mount.

quote:

Originally posted by kimberkid:
…
I just wish they had gotten a 6x like MG34_Dan’s!
...

I got one from IEA back when they offered some for sale. The other came from a private sale up in Dallas.

http://www.mil-optics.de/36/ZF...h0n93q4efhidihcul843

Not sure if you noticed but my mount is exactly like the one in your picture above!

quote:

Originally posted by kimberkid:
Not sure if you noticed but my mount is exactly like the one in your picture above!

Yea, I saw that. IEA was also selling them NIB for 400 Euros.

They can be had between 300 and 400 depending on the adapter type. The base is about 250 the adapter is about 150 depending on type, if it’s STANAG, Weaver, Picantinny, Zeiss or Trijicon.

OK then. I spent the best part of last weekend tearing down and reloading some GP90 ammo from the above lot with SS109 bullets. I used an RCBS kinetic bullet puller to tear down each round, one by one. As each round was torn down



I set aside the pulled GP90 bullet



and refilled the now empty case with the just pulled down powder. I placed an SS109 bullet onto the case mouth



and used a set of RCBS .223 Rem dies to set the bullet to the bottom of its cannelure groove. Interestingly, the original Swiss GP90 cartridge overall length measured 2.240" while that of the newly configured GP90/SS109 ones measure 2.255".



I checked my reloading manuals and the SS109 2.255" COAL is within the acceptable range. I also made sure these cartridges would load into a SIG 550 magazine.

So now we will be able to see how SS109 bullet consistency compares to GP90 bullet consistency.

Some interesting asides; tearing down the GP90 rounds was a real BITCH. I beat the hell out of my kinetic bullet puller. Some rounds could be torn down with just three (3) whacks, but then others took up to twenty two (22) whacks. On average it took nine (9) whacks to disassemble each round. The factory GP90 ammo was placed in the factory ammo box with fifteen (15) rounds per row and six (6) rows deep. The ammo on each row was positioned identically. By alternating each round placement, I was able to easily get sixteen (16) rounds per row and still have six (6) rows deep. I could now hold 96 rounds in a box which is six (6) more the factory boxed ammo.



I also have a plastic bag full of pulled GP90 bullets.

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

kimberkid, this is in no way meant as a complaint, but with all the great information and pics posted since the O.P. started the original topic those interested would have been better served if you had started a separate thread with your initial range report as this thread has evolved well past the topic title...and I very much appreciate the info being added to this subject.

I've never come across a SAN SIG 55X or 550-1 range report that has provided the level of detailed specifics contained in this thread and a dedicated range report thread would have been just the ticket to frame this topic.

quote:

Originally posted by MG34_Dan:
OK then. I spent the best part of last weekend tearing down and reloading some GP90 ammo from the above lot with SS109 bullets. I used an RCBS kinetic bullet puller to tear down each round, one by one. As each round was torn down

I set aside the pulled GP90 bullet

and refilled the now empty case with the just pulled down powder. I placed an SS109 bullet onto the case mouth

and used a set of RCBS .223 Rem dies to set the bullet to the bottom of its cannelure groove. Interestingly, the original Swiss GP90 cartridge overall length measured 2.240" while that of the newly configured GP90/SS109 ones measure 2.255".

I checked my reloading manuals and the SS109 2.255" COAL is within the acceptable range. I also made sure these cartridges would load into a SIG 550 magazine.

So now we will be able to see how SS109 bullet consistency compares to GP90 bullet consistency.

Some interesting asides; tearing down the GP90 rounds was a real BITCH. I beat the hell out of my kinetic bullet puller. Some rounds could be torn down with just three (3) whacks, but then were other that took up to twenty two (22) whacks. On average it took nine (9) whacks to disassemble each round. The factory GP90 ammo was placed in the ammo box with fifteen (15) rounds per row and six (6) rows deep. The ammo on each row was positioned identically. By alternating each round placement, I was able to easily get sixteen (16) rounds per row and still get six (6) rows deep. I could now hold 96 rounds in a box which is six (6) more the factory boxed ammo.

I also have a plastic bag full of pulled GP90 bullets.

Were it me I would have been tempted to keep a small quantity of the GP 90 and shoot it a small sample through the 550-1 (not enough to cause any barrel wear) for a base line reference. It would be interesting to get some real world chrono and accuracy info from it to compare to any other manufacturer or handload data.

Taking one for the team! Looking forward to your range report! Thanks MG34_Dan!

Dan, would it be possible to confirm the lenght of the GP90 projectile please. Only the bullet lenght. This would be great.

quote:

Originally posted by Modern Day Savage:
.
.
.
Were it me I would have been tempted to keep a small quantity of the GP 90 and shoot it a small sample through the 550-1 (not enough to cause any barrel wear) for a base line reference. It would be interesting to get some real world chrono and accuracy info from it to compare to any other manufacturer or handload data.
.
.
.

That's exactly what I intend to do. During my next range session I intend to alternately shoot one group of GP90 ammo and then a group of GP90/SS109 ammo. I'll repeat this pattern as needed. I'm sorry, but I do not have a chronograph to check muzzle velocity.

As I indicated above, some GP90 bullets were seated/glued in place with panache and others were somewhat looser. I wonder if this would have any effect on muzzle velocity? I have no clue. We can all see that the SS109 bullets are clean and identically seated.

Believe me, I'm in no risk of depleting my GP90 stash.

quote:

Originally posted by OTD:
Dan, would it be possible to confirm the lenght of the GP90 projectile please. Only the bullet lenght. This would be great.

I pulled ten (10) random bullets from both the GP90 group and SS109 group. Here are my dial caliper measurements. I'm sorry but I can only get measurements in Imperial (inch) units and not metric units.

GP90 bullet lengths:
.866" - 2
.867" - 4
.868" - 1
.869" - 2
.870" - 1

SS109 bullet lengths:
.906" - 1
.908" - 1
.909" - 2
.911" - 3
.912" - 1
.913" - 1
.914" - 1

quote:

Originally posted by MG34_Dan:

That's exactly what I intend to do. During my next range session I intend to alternately shoot one group of GP90 ammo and then a group of GP90/SS109 ammo. I'll repeat this pattern as needed. I'm sorry, but I do not have a chronograph to check muzzle velocity.

As I indicated above, some GP90 bullets were seated/glued in place with panache and others were somewhat looser. I wonder if this would have any effect on muzzle velocity? I have no clue. We can all see that the SS109 bullets are clean and identically seated.

Believe me, I'm in no risk of depleting my GP90 stash.

OUTSTANDING!

I suspect you are absolutely right and that the variation you found in the GP 90 bullet crimp or sealant will have an affect on the velocity, but without chrono data we'll likely not know.

It's a real shame to go to all the trouble and time you have and not get some real world chrono data to go along with your accuracy and function data...but even so I'm looking forward to your range report results.

Thanks Dan. Imperial is fine. Your data confirm the 22mm I mentioned.

When tearing down GI ammo.....Break the bullet seal by seating the bullet maybe .020-.030 deeper. Makes getting the slug to pull out of the neck MUCH easier.

quote:

Originally posted by FN in MT:
When tearing down GI ammo.....Break the bullet seal by seating the bullet maybe .020-.030 deeper. Makes getting the slug to pull out of the neck MUCH easier.

Sure. Now you tell me. Where the hell were you last Friday evening?

quote:

Originally posted by Modern Day Savage:
kimberkid, this is in no way meant as a complaint, but with all the great information and pics posted since the O.P. started the original topic those interested would have been better served if you had started a separate thread with your initial range report as this thread has evolved well past the topic title...and I very much appreciate the info being added to this subject.

I've never come across a SAN SIG 55X or 550-1 range report that has provided the level of detailed specifics contained in this thread and a dedicated range report thread would have been just the ticket to frame this topic.

<snip>

To be honest, I feel like I've stepped on his thread pretty heavily, but as you've pointed out, with the level of detail from people on this site that have more knowledge and first hand experiance, I'm hoping James in Denver will forgive me ... It certainly wasn't my intent, but sometimes a thread will just explode with great info or entertainment (the "You Will Buy a Glock" thread comes to mind)

BTW, I've been working on my load and reduced it by .5 grains and then group has tightened up considerably. This is a target I shot very quickly on the 25th (another extended lunch) ... The shot in the lower left was shot #2 and it was a flinch this is a target of my own design bot I've copied coppies so many times it's starting to look like I need to re-do it, the white squares are 1" then halved vertically & horizontally but all the horizontals have faded away ... Yeah, I really need to print a new "original"


This last weekend has been pretty crappy weather wise but I'm going to reduce the charge another .3 grains to see if it won't pull in a bit more. I should have done it Monday (Labor Day) as I took the day off even though I should have gone in to work ... I turned my attention to another shiney thing that had my attention and after the rain quit and working in the yard and fixing basement window-well covers and after hearing the wife and daughter were off on their own adventures instead of doing a family thing, I played with a new Binary Trigger ... While it was fun, it doesn't hold a consistent candle to my M16 ... I shook it out with my 11.5" Colt Commando & 10.5" Colt 9mm SMG uppers, CMMG PDW (22LR), Ares Defense 12.5" Beltfed and lastly a generic 8" 300 BlackOut with hyper and sub-sonic ammo.



MG34_Dan, even though I got distracted with another toy ... I'm still looking forward to your groups ... the anticipation of your modified loads is actually making it worse
Weather permitting on Thursday (tomorrow) I hope to shoot a new round of targets with my revised load.

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

Chrono data of the Swiss DoD for GP90 out of a Stgw90 is 905m/s; 2950 fps.

There is plenty of information about accuracy of the 90s/550. Not in English though but just about every club who’s organizing a rifle match is publishing ranking lists with score info. Analyzing the top 10 results for important 300m matches you will get an honest accuracy of 1.5 MOA based on 10 to 18 round strings, always shot prone with the diopter. A decently tuned, free floating AR15 will always outshoot the SIG550.

quote:

Originally posted by OTD:
Chrono data of the Swiss DoD for GP90 out of a Stgw90 is 905m/s; 2950 fps.

There is plenty of information about accuracy of the 90s/550. Not in English though but just about every club who’s organizing a rifle match is publishing ranking lists with score info. Analyzing the top 10 results for important 300m matches you will get an honest accuracy of 1.5 MOA based on 10 to 18 round strings, always shot prone with the diopter. A decently tuned, free floating AR15 will always outshoot the SIG550.

Thanks for that info!
I have to admit using diopters at 300 is a bit intimidating but I'm up for the challange! 17+ years ago I trained and shot Service Rifle matches with an AR and standard sights at 300yards. Back then I only ranked as a Marksman but it was fun and always shooting for a personal best thing. Doing it again does does sound like fun, a personal challange; and as you've noticed I'm not shy about sharing my targets, the good and not so good ... but with diopters it could be pretty ugly, but what the heck!
Anyway, when things dry out I can sent up a 300m target at the farm after they get the milo out ... the range I belong has a 300 but it's up a very steep hill and when it rains, its muddy for weeks. Now days I barely have the lungs to trudge up to 200 in a reasonable amount of time even when its dry. Hardly anyone shoots at 300 ... in fact with all the new shooters the 25 and 50 yard target boards have never been busier ... and they consider 100 yards "long range" ... sometimes its painful to talk to people out there because to listen to them, they know it all ... because they read it on the internet!