1911Forum banner

.45ACP Trajectory Q

1446 Views 7 Replies 4 Participants Last post by  rwmagnus
If using a full size .45ACP (5" barrell) is zeroed for 75 yards (point of aim point of impact) with factory 230gr FMJ RN ammo (say 830fps), what does the trajectory measure out too? What is the lowest/highest point of the trajectory?

I'm guessing at close range 7yds the bullet will hit low (-4")??

Any websites with this info?
1 - 8 of 8 Posts

· Registered
Joined
·
23,961 Posts
I don't know of a website, probably is one somewhere, but I am using the Sierra Infinity program.

If a 230 @ 830 is zeroed at 75 yards, it will be half an inch (0.55") high at 7 yards (How could it be 4 inches low? The bore is only .77" below the line of sight on the gun I figured on and the bullet isn't on a rollercoaster.)
Trajectory peak will be at 3.36" high at 40 yards.

A 50 yard zero might be more practical.
You would only be 1.27" high at 30 yards, on at 50, and 1.44" low at 60. Down 4.62" at 75 yards but that is pretty long pistol shot.
 

· Registered
Joined
·
459 Posts
Discussion Starter · #3 ·
Jim,
Thanks for the insight. I purchased an accurized Les Baer Premeir 2 .45ACP. Didn't have time to adjust the sights yet as it's in the CA cooling off period. Just had time to run 15 rounds thru it mostly checking function. I shot a 10 round timed rate of fire group nice and tight 1" but about 3" low and 3" left. Now I'll admit the owner didn't have the sights adjusted. I'm not sure what the factory zeros the sights for but their accurizing guarantees 1.5" at 75 yards so I'm guessing that's the zero.

no the bullet isn't on a rollercoaster but it's lowest point is the bore then it will rise and fall. I just didn't know what the trajectory looked like. And I also agree a 50 yard zero would be my maximum zero.

On another topic, how do you like the Sierra software? Did you look into the RCBS software? I'm comparing the two right now. Sierra ballistic software can be purchased seperately from the manual but the RCBS has an upgrade to attach to a chronograph.
 

· Registered
Joined
·
23,961 Posts
When did Baer start offering a 1.5" at 75 yard guarantee? Last I looked it was at 50.

I can't compare software packages, I bought the Sierra Infinity on sale and it is ok for my use so I have not bought another. It is nearly as good as the freeware Q-Ball I used until some sort of file corruption on my computer trashed it.

However, I need to call Sierra and complain. The ballistics side of the package works but I found just the other day that I cannot call up load data. I did not know, because I am a lot more likely to pick up a manual to look up a load than to fire up the computer.
 

· Registered
Joined
·
459 Posts
Discussion Starter · #5 ·
My bust on the yardage it's 50 yards.

Sierra software looks pretty good. Calling up load data is critical unless you are always using stock data covered in the software. Having it link to a chronograph would be a nice feature just not sure it's necessary for pistol stuff.

I think the retail on the Sierra software is $39 very reasonable. RCBS is $99.
 

· Registered
Joined
·
1,303 Posts
RW;
Just by coincidence many of my older 1911s are zeroed at 75 yards (since I live in a rural area and they do double duty as hunting and defense guns).

While I have often found that ballistics charts are off a bit (at least for rifles at really long range) the figures Jim W. gave are almost spot on. I don't pay much attention to the fractions of an inch at 7 yards...they seem to hit dead on at 10 yards for me. 2.5" high at 25 yards, 3.5" high at 37 yards and 4" low at 100. Of course those are not perfect since I cannot shoot "one hole groups" way out there.

I did a test once, trying to justify purchasing a 10mm, and shot targets with a 1" piece of tape across the center of the A-zone at 25, 50, 75 and 100 yards with a 6" .357 mag, 6.5" .44 mag., 5" 10mm and 5" .45 all zeroed at 75 yards. The resultant groups showed me that there was not enough difference to even worry about - to be sure, the .357 and .44 were centered slightly higher but not enough to make a difference on a man or a deer (now on a ground hog it may have mattered).

Of course I went ahead and bought the 10mm anyway:rolleyes:

Cordially,
Jim Higginbotham
 
1 - 8 of 8 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top