Survivalist Forum

Advertise Here

Go Back   Survivalist Forum > Firearms and Other Weapons Forum > Military Weapons Forum
Articles Chat Room Classifieds Donations Gallery Groups Links Store Survival Files



Military Weapons Forum AR15, AK47, SKS, H&K, Galil, CETME, FN/FAL, Tanks, Ships, Jets, Helicopters....

Advertise Here
Reply
 
Thread Tools Display Modes
Old 01-25-2011, 11:27 PM
GramercyRiff's Avatar
GramercyRiff GramercyRiff is offline
Prepared
 
Join Date: Jan 2010
Location: NJ
Posts: 354
Thanks: 205
Thanked 232 Times in 115 Posts
Default Sighting in 7.62x39 Rifle at 25 yards.



Advertise Here

I have a couple of 7.62x39 rifles with 16" barrels that have never been properly sighted in. The nearest 100+ yard rifle range is about an hour and a half from my house. When they are not closed for cleaning/construction, there is a line waiting to get in. I do have an indoor 25 yard public range close by that will allow rifles and steel-cased ammo.

Can anyone give me an idea of where my shots should be landing at 25 yards to approximately sight in for 100 or 200 yard shots? (2" high, 3" low ?)

I tried to read some ballistic charts and tables but got more confused the more I read. Does the 7.62x39 arc or just drop? I realize this method won't replace actually sighting in at 100 yards but I'd be happy if someone could get me in the general ball park.
Old 01-26-2011, 12:42 AM
CrypticCRICKET's Avatar
CrypticCRICKET CrypticCRICKET is offline
Freedom isn't free.
 
Join Date: Nov 2010
Location: Region 4 - beseiged by communists/ corporate fascists/ criminals...
Posts: 4,204
Thanks: 4,269
Thanked 7,493 Times in 2,530 Posts
Default

When you fire a bullet from a barrel it drops in an arc from the original flight path. When bullets travel higher than the point of aim in their arc towards the target it's because the initial flight trajectory has been adjusted to account for bullet drop at target distance. The height of a guns sights off the bore of the barrel has to be added into any bullet trajectory calculation.

I did a quick calculation using a 123 grain bullet at 2329 fps with a 1.7" sight height and a 100 yd zero and the calculator pooped out a 25 yd impact at .55 inches below the zero aimpoint at 100 yds. At 75 yards the bullet impacts .36 inches above the zero aimpoint at 100 yds. At 100 yds it's loosing altitude again as it comes in on target zero. At 200 yds the bullet mpacts 8.5 inches below the 100 yard zero.

The SKS will shoot to different aimpoints depending on how it's rested and how much downward pressure you apply to the forearm of the rifle. Poor quality control in ammo manufacturing also makes it hard to sight in accurately. Typical impact spread at 100 yds is 1.5 to 2.5 inches when you've sorted your ammo by length to get rounds that are all the same length. Good luck.
The Following 2 Users Say Thank You to CrypticCRICKET For This Useful Post:
Old 01-26-2011, 07:53 PM
res45's Avatar
res45 res45 is offline
Boolit Master
 
Join Date: Dec 2008
Age: 55
Posts: 1,150
Thanks: 246
Thanked 1,010 Times in 555 Posts
Default

The SKS is equipped with a BSZ Battle Site Zero setting. To set this raise the sight ladder and pull the slide adjuster all the way to the rear so it rest on the raised portion of the rear sight housing,this is represented by the various characters such as a -U- or -III- on the rear of the sight ladder behind the 100 meter mark.

At 100 meters/109 yds. using a 123 gr. bullet adjust the front sight for evaluation and windage so your point of impact is 2.9" above your point of aim. With that setting you should be able to hit center mass from 0 out to 225 meters or 250 yds.
The Following User Says Thank You to res45 For This Useful Post:
Old 01-26-2011, 10:00 PM
Sprout47's Avatar
Sprout47 Sprout47 is offline
Formerly Known as GOFO
 
Join Date: Jan 2009
Location: The Bat Cave
Age: 36
Posts: 2,893
Thanks: 2,093
Thanked 3,715 Times in 1,704 Posts
Default

Typically at 25 yds. POI should be 1.5" below POA for a 100yd. zero.

Read that somewhere... can't remember now but there are AK zero targets floating around the Web somewhere that have that set-up for you - or get a 25m M16 target and aiming centermass your rounds should impact at the base of the silhouette.
Old 01-26-2011, 10:03 PM
Sprout47's Avatar
Sprout47 Sprout47 is offline
Formerly Known as GOFO
 
Join Date: Jan 2009
Location: The Bat Cave
Age: 36
Posts: 2,893
Thanks: 2,093
Thanked 3,715 Times in 1,704 Posts
Default

And to answer your question, all bullets Arc.

I tend to enjoy a 100 yd. zero on all my rifles, shoots low out to 100 and drops from there, where as a 25 yd. zero will have rise out to about 220 yds. and then all drop from there out.

I would keep a notepad and record some data when you go shooting.
The Following User Says Thank You to Sprout47 For This Useful Post:
Old 01-26-2011, 10:09 PM
Sprout47's Avatar
Sprout47 Sprout47 is offline
Formerly Known as GOFO
 
Join Date: Jan 2009
Location: The Bat Cave
Age: 36
Posts: 2,893
Thanks: 2,093
Thanked 3,715 Times in 1,704 Posts
Default

http://www.ak-47.net/ak-47/sightingin.php
Old 01-27-2011, 10:49 AM
shamalama's Avatar
shamalama shamalama is offline
Prepared
 
Join Date: Mar 2010
Location: near Atlanta, GA, USA
Age: 54
Posts: 274
Thanks: 175
Thanked 337 Times in 117 Posts
Default

Per data from Federal Ammunition:

If you zero at 100 yards, then 50 yards will be +0.1" and 200 yards will be -6.5"

If you zero at 200 yards, then 50 yards will be +1.8" and 100 yards will be +3.3"
The Following User Says Thank You to shamalama For This Useful Post:
Old 01-27-2011, 01:54 PM
Amra910's Avatar
Amra910 Amra910 is offline
"Not vengence Punishment"
 
Join Date: Jan 2009
Location: Republic of Texas
Posts: 1,257
Thanks: 3,398
Thanked 957 Times in 489 Posts
Default

Quote:
Originally Posted by GramercyRiff View Post
I have a couple of 7.62x39 rifles with 16" barrels that have never been properly sighted in. The nearest 100+ yard rifle range is about an hour and a half from my house. When they are not closed for cleaning/construction, there is a line waiting to get in. I do have an indoor 25 yard public range close by that will allow rifles and steel-cased ammo.

Can anyone give me an idea of where my shots should be landing at 25 yards to approximately sight in for 100 or 200 yard shots? (2" high, 3" low ?)

I tried to read some ballistic charts and tables but got more confused the more I read. Does the 7.62x39 arc or just drop? I realize this method won't replace actually sighting in at 100 yards but I'd be happy if someone could get me in the general ball park.

Here is a range card for you. It is 100 yd zero. According to it when aiming at bulls eye the impact will be .7" below point of aim. I got all the information from Wolf so I could enter it into the program.

The Following 2 Users Say Thank You to Amra910 For This Useful Post:
Old 01-27-2011, 05:54 PM
res45's Avatar
res45 res45 is offline
Boolit Master
 
Join Date: Dec 2008
Age: 55
Posts: 1,150
Thanks: 246
Thanked 1,010 Times in 555 Posts
Default

http://www.ak-47.net/ak-47/sightingin.php
The Following User Says Thank You to res45 For This Useful Post:
Old 01-27-2011, 07:21 PM
HorseSoldier HorseSoldier is offline
Hiker
 
Join Date: Jan 2011
Location: ANC AK
Posts: 725
Thanks: 237
Thanked 652 Times in 381 Posts
Default

Quote:
The SKS is equipped with a BSZ Battle Site Zero setting.
This. Zero at 25 meters on the battle sight setting. Then set your sight on the 100 meter setting and don't move it again (100 meter setting will give you better accuracy out to about 200 meters than the battle sight setting).
The Following User Says Thank You to HorseSoldier For This Useful Post:
Old 01-27-2011, 07:42 PM
jason1221 jason1221 is offline
Recent Blog:
Survivor
 
Join Date: Feb 2009
Location: was C.T. now middle TN
Posts: 2,463
Thanks: 1,568
Thanked 1,274 Times in 748 Posts
Default

Quote:
Originally Posted by GramercyRiff View Post
I have a couple of 7.62x39 rifles with 16" barrels that have never been properly sighted in. The nearest 100+ yard rifle range is about an hour and a half from my house. When they are not closed for cleaning/construction, there is a line waiting to get in. I do have an indoor 25 yard public range close by that will allow rifles and steel-cased ammo.

Can anyone give me an idea of where my shots should be landing at 25 yards to approximately sight in for 100 or 200 yard shots? (2" high, 3" low ?)

I tried to read some ballistic charts and tables but got more confused the more I read. Does the 7.62x39 arc or just drop? I realize this method won't replace actually sighting in at 100 yards but I'd be happy if someone could get me in the general ball park.
Show me your groups and i can help you.At 25 yards you shouldn't be to far off maybe few inches up down sometimes the manaul will show the bullet drop.You also may want to look up 100 meters 200 meters.If your rifle is other than american it's in meters.
Show me a picture and i may be able to help.
The Following User Says Thank You to jason1221 For This Useful Post:
Old 01-27-2011, 11:17 PM
GramercyRiff's Avatar
GramercyRiff GramercyRiff is offline
Prepared
 
Join Date: Jan 2010
Location: NJ
Posts: 354
Thanks: 205
Thanked 232 Times in 115 Posts
Default

Thanks for all the great info. I won't make it to the range till next week but look forward to sighting these things in.

In addition to attempting to zero the rifles, I'm bringing a few hundred rounds of several different ammo brands (Wolf, Golden Tiger, Silver Bear, Brown Bear, etc) and bullet types (HP, SP, FMJ) to make sure I know what my rifles like and which brand to stock up on. I'll keep notes and post any interesting findings.
Old 01-28-2011, 12:47 AM
wfokarr wfokarr is offline
Reverse Polarity
 
Join Date: Dec 2010
Location: Central Kentucky
Age: 51
Posts: 114
Thanks: 53
Thanked 49 Times in 32 Posts
Default

Regardless of Ballistic charts a rifle will generally shoot the same trajectory at 100 yds. as 25 yds. That's how I have set my sights for 30 some odd years.Works for me.
Old 01-28-2011, 08:58 AM
wldrbob's Avatar
wldrbob wldrbob is offline
Hiker
 
Join Date: Dec 2010
Location: northeren manitoba
Posts: 739
Thanks: 171
Thanked 776 Times in 346 Posts
Default

Quote:
Originally Posted by wfokarr View Post
Regardless of Ballistic charts a rifle will generally shoot the same trajectory at 100 yds. as 25 yds. That's how I have set my sights for 30 some odd years.Works for me.
maybe with iron sights.... not happening with a high scope mount like those see through mounts ..right on at 25 will be pretty high at distance i have one gun set up with those.
Old 01-28-2011, 09:13 PM
Sumi Sumi is offline
Newbie
 
Join Date: Jan 2011
Posts: 10
Thanks: 5
Thanked 5 Times in 3 Posts
Default

Thank you, I was looking for this site =]
Old 01-28-2011, 09:20 PM
Jeffrey's Avatar
Jeffrey Jeffrey is offline
Opinionated old fart.
 
Join Date: Nov 2008
Location: South Carolina
Age: 47
Posts: 8,044
Thanks: 1,261
Thanked 6,988 Times in 3,332 Posts
Default

I dont (currently) have a 7.62x39, but I set my sights at Battle sight Zero (25m)for four reaons:
1. Thats what the military uses.
2. Thats what my military sights are designed for.
3. Thats the distance from my front door to street.
4. Thats the distance from my back door to fence.
The Following User Says Thank You to Jeffrey For This Useful Post:
Reply

Bookmarks



Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
sighting in Rifle question (ak) Sloth Rifle Forum 21 01-23-2011 09:50 PM
Which .22 rifle for combat training at 100 yards? FloridaState Firearms General Discussion 15 04-26-2010 11:42 PM
Sighting in a rifle made easy randkl Firearms General Discussion 3 12-29-2009 10:08 PM
Sighting in of Rifle Scopes - Long read T191032 Rifle Forum 0 01-04-2009 10:48 PM
Help with sighting in a rifle Nivek Rifle Forum 11 11-29-2008 08:43 PM


All times are GMT -5. The time now is 05:04 PM.


Powered by vBulletin®
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright Kevin Felts 2006 - 2012,
Green theme by http://www.themesbydesign.net