How many yards you think the Springfield Edge will shoot acutely? I’ll put a red dot with a magnifier. Not sure yet though! Thanks guys...

Probably no more or no less than a comparable gun.

Is this a trick question?

In open deep space?

To INFINITY & BEYOND!!!

Here on Planet Earth, usually about out to 150 to 200 meters depending on your stance - rest - ammo.

The AR "Pistols" CAN be surprisingly accurate, but those shorter barrels loses a lot of ZIP from 5.56, making the effective defense range (fragmentation or expansion of bullet) fairly short compared to a 16" or 20" AR.

BIGGER_HAMMER

Not a trick question I just have more in life than guns. So please just be nice and help me out. I have a Holosun HS510C for it but was thinking of adding a magnifier. Please help if possible or not? Or should I throw on a Vortex, Eotech, or Sig???

This page will give you an idea of what you can expect in velocity from the short barrel.  If you plug your velocity and load info into this calculator you will have an idea of the effective range and trajectory curve.  

I did a rough estimate for you, it should be close:

Bullet StylenullBullet Weight (grains)55 grs
G1 Ballistic Coefficient.3Muzzle Velocity2,300 fps
Sight Height2.6 inZero Range50 yd
Temperature59 °FWind Speed10 mph
Altitude0 feetMax Range400 yd
RANGE (YD)DROP (IN)WIND DRIFT (IN)VELOCITY (FPS)ENERGY (FT-LB)
0     -2.6     0.0   2300 646
25   -1.1     0.1   2232  608
50    0.0     0.4   2164  572
75    0.6     0.9   2098  538
100   0.7    1.5   2033  505
125   0.4    2.3   1969  473
150  -0.6    3.3   1906  444
175  -2.1    4.6   1845  415
200  -4.3    6.2   1785  389
225  -7.2    8.0   1727  364
250  -10.9  10.1  1670  341
275  -15.3  12.5  1615  318
300  -20.5  15.0  1561  298
325  -26.5  17.8  1508  278
350  -33.6  20.9  1458  259
375  -41.7  24.4  1410  243
400  -51.0  28.2  1364  227

As you can see you should still be supersonic beond 400 yards, but effective range will be questionalble beyond 200 depending on the projectile as most expanding bullets require around 1,800 fps to work.  A magnifyer would be usefull, but they magnify the reticle as well as the target image.  For man size targets not a problem, but if you may need to use it for small targets an LPVO or prism might be better.  Hope this helps.

The local gun shop has one of these in stock.  The price is stupid, the gun is probably stupid but I still want one for some reason.

ACCURATELY ???

Well with the EVAC you've also got to worry about the removable barrel affecting accuracy, and zero especially.

If one is going to use as a take-down I think iron sights would be the way to as I wouldn't trust an optic without checking zero.  At least a front sight will index with the muzzle and should be pretty damn consistent.

G & A did a review:https://www.gunsandammo.com/editorial/springfield-saint-edge-pdw-ar-pistol-review/375352

2.5 to 4 MOA at 100 yds.

leave off the magnifyer

Still haven’t bought one but I’ve bought more boom booms??. I won’t get a magnifier thought, thanks!

Barrel length and accuracy or not related.

I have the SA Edge Evac and SA Victor PDW. I was shooting/zero'ing them at 25, 50, and 100 yards a few days ago. At 25 yards they had decent accuracy. At 50 they were starting to spread, with the Evac being a tighter group than the PDW. At 100 neither was great, but I was using non-magnified Sig and Holosun red dots.

I bought them because they're cool as all hell, and for CQB. They are LOUD though, and unsupressed, inside a home at night... it would be like a flash bang! I also took my regular SA Saint Victor 5.56 AR pistol and my old school Bushmaster 20" A2 HBAR, so I could compare loudness between all of them. The Bushy was a pussy cat, and far more accurate at distance than the other three pistols. The three SA pistols were equally loud between all three, but each had a different sound. The Evac and PDW had more recoil than the others. I also have SA Saint Victor pistols in .300 Blackout and .308. They're awesome too, but I left them home because I wanted to compare apples to apples. My CMMG Guard in 9mm isn't relevant here, but would be my #1 choice to use inside my home of a few other CQB scenarios.

My black guns are my "babies" and frankly, I'm thinking about selling my 2005 SA M1A Standard and my November 1943 SA M1 Garand, because though they are awesome, they just don't enter into my sphere of interest at the moment. I should probably keep the Garand though. It's all original parts and may have seen combat (the stock is pretty worn). But actual current, useful and capable fighting handguns, pistols, and rifles are what I care about right now. The other stuff is really just safe queens. Don't get me wrong... the Garand and M1A are very battle-capable rifles, but they're not on the list of guns I would load-out with in a SHTF scenario. My AR pistols and one of my .308 bolt rifles would be in my kit... along with one of my S&W M&P 9 sidearms.