FN Herstal Firearms banner

1 - 10 of 10 Posts

·
Registered
Joined
·
32 Posts
Discussion Starter · #1 ·
I have been searching the forums and I have not been able to find what I am looking for.

Does anyone have any range reports on the group difference on a PS90 from the standard barrel and the 10.3" SBR?

I am looking at 100 yards for the zero.

I have an SBR upper with an Aimpoint CompM3. I want to put an ACOG TA31DOC or TA01NSN on it(already have both). With a magnified scope I will be more likely to make a 100 yard shot and was curious about any major difference in accuracy at 100 yards.

This is for LE use.

If I missed the post, a reroute would be appreciated.
 

·
Registered
Joined
·
15,559 Posts
That is a good question - I have sene people who have short barrelled the gun state that the gunw as just as accurate - but I have yet to see anyone post exact numbers - before and after group sizes. That would be good info to have - but someone would have had to have the forethought to test the gun before changing the barrel.
 

·
Registered
Joined
·
520 Posts
general laws of ballistics say that the longer barrel will be more accurate, but i know the PS90 was designed with the 10.3" barrel. i don't have my PS90 yet, but i would still venture to say that the 16" barrel would be more accurate.

that all said, i do plan on SBRing mine eventually. if we don't have an anwer by then, i will be sure to get some numbers down.
 

·
Registered
Joined
·
32 Posts
Discussion Starter · #4 ·
I sent an email to FNH direclty asking the below question. The smaller barrel is great as an entry tool. I am just curious how much the shorter barrel effects a longer shot vs the longer barrel.

If no one responds with an answer, I can do my own testing on the SBR version and see what kind of groups I get. If I am able to get acceptable groups at 100 yards, for LE purposes, then I will keep it an SBR.

Obviously the longer barrel is more accurate and allows for the gases to expand more increasing velocity. I just want to know to what extent.

At 50 yards I was punching holes through metal doors with SS190 ammunition. I get great groups at 50 yards, but due to a 4MOA Aimpoint I can't truly test accuracy at 100 yards. As soon as I swith to a 4x32 ACOG I should be able to.

Either way I can forward my data to these forums and hopefully someone will do the same with the standard barrel length at 100 yards, for an unofficial comparison.

I was hoping the PS90 had been out long enough for the question to be already answered.
 

·
Registered
Joined
·
15,559 Posts
I've gotten 1/2 inch groups at 50 yards - My eyes suck at 100 yards - so with an Eotech - I don't even count it as a group - that's not the guns issue - its me, though
 

·
Registered
Joined
·
520 Posts
i'm the exact same way. i can hit MOD (minute of dead) at 100yds, but any real accuracy would require a magnified optic.
 

·
Administrator
Joined
·
11,940 Posts
Procinctu said:
I have been searching the forums and I have not been able to find what I am looking for.

Does anyone have any range reports on the group difference on a PS90 from the standard barrel and the 10.3" SBR?

I am looking at 100 yards for the zero.

I have an SBR upper with an Aimpoint CompM3. I want to put an ACOG TA31DOC or TA01NSN on it(already have both). With a magnified scope I will be more likely to make a 100 yard shot and was curious about any major difference in accuracy at 100 yards.

This is for LE use.

If I missed the post, a reroute would be appreciated.
Give me about a couple of weeks and I'll be able to answer your questions. I should have my short barrel by then. I already have the Form 1 and the engraving done on the second receiver that I have so when I do get the short barrel, I'll have both the PS90 and the PS90SBR uppers to switch out as I please.

I intend to chrony some test rounds that I am developing thru both firearms. I will also do target analysis at various distances of the same type of round fired from both weapons. Both firearms will have laser signts on them so targeting should not be a problem. Of course I do not have access to SS190 ammunition so my information will be based on the 30g, 40g, and 55g ammunition that I load myself, as well as some data from SS197SR, SS195, and SS192 ammo.
 

·
Registered
Joined
·
32 Posts
Discussion Starter · #8 ·
Perfect. As soon as my ACOG mount comes in I will zero it as an SBR.

If your tests show significant increases at 100 yards, I may buy a second receiver with longer barrel and keep the SBR upper for entries.

If I can get hold of a chrono I can test the SS190 velocity on the SBR at least.

My current SBR is using an Aimpoint CompM3 (TROS mount) and TLR-1 with pressure switch.

 
1 - 10 of 10 Posts
Top