Question for Primary Arms users

[Robinhood]

Thanks for the feedback Blue. PA is less than 15 miles from me and I was going to drop by today and look them over.

[Russ77]

I just ordered one today. Can't wait to get my hands on it

[Russ77]

One thing I can't figure out on the reticle is the jump from 100 to 200 yards is very small. Then when you go from 200 to 300 yards the jump is large?is the drop from 100 to 200 that small in comparison to the 200 to 300 mark? It does not seem to add up

[foxx]

One thing I can't figure out on the reticle is the jump from 100 to 200 yards is very small. Then when you go from 200 to 300 yards the jump is large?is the drop from 100 to 200 that small in comparison to the 200 to 300 mark? It does not seem to add up

Because the bullet drops maybe an inch from 100 to 200 and 2 inches from 200 to 300 and then maybe 5 inches from 300 to 400, then 10 inches from 400 to 500 yards. Those are not actual amounts, just trying to illustrate that, as the bullet slows down, it falls more and more before reaching the next 100 yards... take a look at a bullet trajectory chart and you will see the bullet path is not a straight line but a curved line. Final example, consider an arrow's flight. If you shoot an arrow at a target 20 yards away, and compare how much higher you must aim at 30 yards versus 40 or 60 yards. The hold-over is progressively and relatively higher and higher the further out you go.

[BlueDog]

Foxx nailed it. Gravity is a helluva thing. I once was told that a 308 wasn't worth shooting because "it jumps straight up out of the barrel"... I talked myself blue in the face trying convince this guy that ALL bullets begin dropping immediately after leaving the barrel. And the bevaviour he was referring to was the slight upward angle of the barrel in opposition to the scope (it aims "down"). The 308 didn't shoot as flat as this guys "7mag" (which by the way reportedly shot flat as a laser) and in turn the barrel was angled up higher to lob the bullet to the same point of impact. I was informed I was dead wrong. Physics don't lie, but they sure are fascinating.

[foxx]

another way to look at it...

due to gravity, all objects fall in a vacuum at a constant rate or speed of 32 feet per second squared...
Because they lack wings, all bullets start falling the moment they leave the barrel (assuming your rifle is level when fired). It takes a split second to reach 100 yards, but even then, gravity has pulled your bullet down a bit in that short time span...

Because of air resistance, the bullet starts to slow down as soon as it leaves the barrel. the farther it goes, the more it slows down. Eventually it would actually stop and drop if it didn't hit the ground first...

it takes longer for it to go from 100 to 200 then it did 0 to 100. In that slightly longer bit of time, gravity pulls it down a bit more than the first 100 yards. It keeps getting slower and slower, allowing more TIME for gravity to pull it down further while it's traveling the same DISTANCE to the next target. Eventually it just hits the ground.

[DrThunder88]

More than that, gravity causes acceleration. Not only does the slowing bullet have more time to fall, it's falling faster with time!

[robtattoo]

If you really want a physics mind blow....
Forward momentum has zero bearing on gravity's effect on drop.
If you shot a 175gn bullet at 3000 fps from a barrel that is perfectly level, whilst simultaneously dropping a static 175gn bullet from the exact high of the center line of the barrel, they would impact the ground at exactly the same moment.
Skadoosh.

[BlueDog]

Since this has become a science lesson, (lol) another mind blowing factoid is the bullet never actually touches the barrel. In turn you have never truly "touched" anything. Quantum mechanics shows us there is space (really really really super tiny space) between objects. We live in an amazing universe, things like the "observer effect" where the mere act of observing something can change its value, or if we try to measure light we change it from what is was. OR "entanglement", where different particles exist and then don't and can relate to other particles in a seperate timeline (past or future)... Yikes!

So yes, I really like my Primary Arms scope (even though I've never actually "touched" it)

[rfd12fv]

i have a very very similar scope to the pa 4-14x44, the sun optics 4-14x44 (ffp and sf), but costs over $100 more (street price). it's on the axis hb .308win. maybe it's the same as the pa, but i've read that the sun glass is better (?). if i knew about the pa i probably would have opted for it over the sun. after all, the axis is just a bottom feeder cheap rifle. :devilish:

http://sunopticsusa.com/products/first-focal-plane-30mm-tactical-hunter-rifle-scope/CS-4141444


http://i.imgur.com/4tnv1xC.jpg

[Russ77]

Wow that rifle looks great! Did you have the muzzle threaded or is the flash suppressor booted on?

[Russ77]

Got home and my scope was waiting for me in the living room. Wow this thing is a lot bigger than I thought it would be. Everything looks great on it. When I turn the light up reticle on it looks like I'm seeing two of the center horse shoes that light up in red very close together. Am I just not lining up straight on the scope??

[rfd12fv]

Wow that rifle looks great! Did you have the muzzle threaded or is the flash suppressor booted on?

it's a muzzle brake by witt machine, bolted on (see the three bolts at its bottom?).