HuntingNut
HuntingNut
   Login or Register
HomeCommunity ForumsPhoto AlbumsRegister
     
 

User Info

Welcome Anonymous


Membership:
Latest: Pavel
New Today: 1
New Yesterday: 0
Overall: 12456

People Online:
Members: 0
Visitors: 75
BOT: 4
Total: 79
Who Is Where:
 Visitors:
01: Forums
02: Forums
03: Forums
04: Forums
05: Forums
06: Forums
07: Forums
08: Forums
09: Forums
10: Forums
11: Forums
12: Forums
13: Forums
14: Forums
15: Forums
16: Forums
17: Forums
18: Forums
19: Forums
20: Forums
21: Forums
22: Forums
23: Forums
24: Forums
25: Forums
26: Forums
27: Forums
28: Forums
29: Forums
30: Forums
31: Forums
32: Forums
33: Forums
34: Forums
35: Forums
36: Forums
37: Forums
38: Forums
39: Forums
40: Forums
41: Your Account
42: Forums
43: Forums
44: Forums
45: Forums
46: Forums
47: Forums
48: Forums
49: Forums
50: Forums
51: Forums
52: Forums
53: Forums
54: Forums
55: Forums
56: Forums
57: Forums
58: Forums
59: Forums
60: Forums
61: Forums
62: Forums
63: Forums
64: Forums
65: Forums
66: Forums
67: Forums
68: Forums
69: Forums
70: Forums
71: Forums
72: Forums
73: Forums
74: Forums
75: Forums
  BOT:
01: Forums
02: Forums
03: Forums
04: Forums

Staff Online:

No staff members are online!
 

Coppermine Stats
Photo Albums
 Albums: 302
 Pictures: 2369
  · Views: 293411
  · Votes: 1299
  · Comments: 86
 

Support our Advertisers

How many of you understand a scopes "subtend"
Discussions related to Guns and Firearms

View previous topic :: View next topic  
Author Message
DallanC
Site Admin
Site Admin


Joined: Jan 18, 2005
Posts: 3141
Location: Utah

PostPosted: Fri Feb 10, 2006 6:33 pm    Post subject: How many of you understand a scopes "subtend" Reply with quote

How many of you understand a scopes "subtend"? I know there are alot of guys here who do (huntingnut has more knowledgable people) but it seems there are an awfully lot of people who dont have a clue what it is and how it can be used to not only estimate ranges, but wind, leads, holdover etc etc.

I'm thinking about writing a comprehensive guide one of these days on it.


-DallanC
Back to top
View user's profile Photo Gallery
Dimitri
Super Member
Super Member


Joined: Nov 25, 2005
Posts: 5906
Location: Southern Ontario

PostPosted: Fri Feb 10, 2006 7:22 pm    Post subject: Re: How many of you understand a scopes "subtend" Reply with quote

DO IT!

I've got no idea how to do it execpt that if you bracket a known size at a known distance at a certian maginfication you can "guesstamate" Razz

Help! Help

Dimitri

_________________
A thousand hills, but no birds in flight, ten thousand paths, with no people's tracks. A lonely boat, a straw-hatted old man, fishing alone in the cold river snow.
Back to top
View user's profile Visit poster's website Photo Gallery
roklok
Super Member
Super Member


Joined: Aug 11, 2005
Posts: 607
Location: Fairbanks, Alaska

PostPosted: Fri Feb 10, 2006 7:53 pm    Post subject: Re: How many of you understand a scopes "subtend" Reply with quote

My Leupold Vari-X 3 3.5-10 on my .243 has two sets of digits marked on power ring,one of course is power the other is the estimated distance to the target by bracketing a 16 inch target between the crosshairs and the thicker point of the duplex reticle. On my .35 Whelen with 2-7 leupold I use the lower point of the duplex reticle as my 350 yard aiming point at 7 power.0-250 yards I aim using crosshairs,300 I aim midway between crosshairs and point,350 use the point,and 400 put point on the top of back.I have never had the opportunity to fire at an animal at this distance(big game) but have practiced this a good deal and have turned in some pretty respectable groups at 400 yards with my whelen and 7 power scope. I just called Leupold last week to see if their custom shop could install their long range duplex reticle or their new ballistically matched reticle in my scope but was dismayed to learn that they can only do that to their new VX series. So I guess I will continue using this system.
Back to top
View user's profile
roklok
Super Member
Super Member


Joined: Aug 11, 2005
Posts: 607
Location: Fairbanks, Alaska

PostPosted: Sat Feb 11, 2006 5:01 pm    Post subject: Re: How many of you understand a scopes "subtend" Reply with quote

Its too bad that scope manufactures dont give the MOA of the reticle from center to thick portion at highest power. I know its easy to figure this out if using a 1 inch grid target at 100 yards but I dont normally keep such targets on hand,preferring to shoot at a simple 1 inch square black sticker on a sheet of white paper.
Back to top
View user's profile
Coyote_Hunter_
Member
Member


Joined: Mar 05, 2005
Posts: 208
Location: Franktown, CO

PostPosted: Sun Feb 12, 2006 7:42 am    Post subject: Re: How many of you understand a scopes "subtend" Reply with quote

I've been using Duplex reticles as rangefinders for quite a few years. These days I use a laser for accuracy but often use the reticle for fun.

_________________
Coyote Hunter
NRA, GOA, DAD
Back to top
View user's profile Photo Gallery
Gil Martin
Super Member
Super Member


Joined: Jan 28, 2005
Posts: 1600
Location: Schnecksville, PA

PostPosted: Sun Feb 12, 2006 7:54 am    Post subject: Re: How many of you understand a scopes "subtend" Reply with quote

It depends. I think this would be a good topic to cover. Around here, really long shots are rare, except for groundhogs and perhaps deer. We tend to sight in a bit high at 100 yards and work with a point-blank hold. All the best...
Gil

_________________
Gil
Back to top
View user's profile
sniper
Super Member
Super Member


Joined: Aug 18, 2005
Posts: 735
Location: Utah

PostPosted: Mon Feb 13, 2006 12:29 am    Post subject: Re: How many of you understand a scopes "subtend" Reply with quote

DallanC wrote:
How many of you understand a scopes "subtend"?
-DallanC

If my understanding is correct, it is simply a big word to describe how much the scope reticle will cover at distances.

If the crosshair intersection will cover a 1 in. object at 100 yds, it is a 1" subtension. (Did I spell that correctly?)

Or could it also be used also for the thick/thin portions of the duplex reticle, too? Where the reticle goes from wide to skinny on either side of the intersection could be said to subtend 12" at 100 yds, I think, but that varies by manufacturer. It could be used as an approximate rangefinder.

If your crosshairs completely cover an object, it's generally too far/small to shoot at with reasonable expectation of success. Just my $.02
Back to top
View user's profile
Spacedone
Member
Member


Joined: Nov 04, 2005
Posts: 266
Location: missouri

PostPosted: Mon Feb 13, 2006 8:46 am    Post subject: Re: How many of you understand a scopes "subtend" Reply with quote

ok lets see if i understand this properly.

i look at the target and see the crosshairs and guesstimate the size of the target then guess my small recticle part is 18 inches at 100 yards and im at 300 yards so i carry the 2 and divide by 27 then add 9 and find the square root of 105 then subtract 33 and miss my target by the angle of a large lighthouse.
Back to top
View user's profile MSN Messenger
roklok
Super Member
Super Member


Joined: Aug 11, 2005
Posts: 607
Location: Fairbanks, Alaska

PostPosted: Mon Feb 13, 2006 9:52 am    Post subject: Re: How many of you understand a scopes "subtend" Reply with quote

Leupolds standard duplex in their 3.5-10 has about a 2.66 MOA thin portion from intersection to thick point at 10 power.But of course as stated this varies by brand and also by magnification.
Back to top
View user's profile
sniper
Super Member
Super Member


Joined: Aug 18, 2005
Posts: 735
Location: Utah

PostPosted: Mon Feb 13, 2006 10:59 am    Post subject: Re: How many of you understand a scopes "subtend" Reply with quote

Spacedone wrote:
ok lets see if i understand this properly.

i look at the target and see the crosshairs and guesstimate the size of the target then guess my small recticle part is 18 inches at 100 yards and im at 300 yards so i carry the 2 and divide by 27 then add 9 and find the square root of 105 then subtract 33 and miss my target by the angle of a large lighthouse.

Very Happy By George, I think you've got it! Very Happy If you can see it without the crosshairs covering it, SHOOT! Then compensate, then shoot again.....Then... Shooting Razz

Most manufacturers list the reticle statistics, including what we are talking about on the info sheet that comes with the scopes. You know, the one with the instructions we either throw away or put in the scope box and never see again? Now... where DID I put that scope box? Wink
Back to top
View user's profile
Dawgdad
Super Member
Super Member


Joined: Feb 08, 2006
Posts: 1041
Location: On the Prairie

PostPosted: Mon Feb 13, 2006 4:38 pm    Post subject: Re: How many of you understand a scopes "subtend" Reply with quote

I have known that and used it on some scopes, but have found that I never reallly had time to check the magnification on my variable scopes when the shot presented. I usually range the terrain before the game shows up and set my maximum PBZ by a tree or a bush and do not shoot beyond that. (Of course that is all about to change if you read my thread in relaoding section)

My illuminated mildots are pretty slick for low light range guestimating with a Mildot master in my cargo pocket.

_________________
Alcohol, Tobacco and Firearms should be a convenience store, not a government agency...
Back to top
View user's profile Photo Gallery
Flint54
Member
Member


Joined: Apr 09, 2005
Posts: 389
Location: North Carolina

PostPosted: Tue Feb 14, 2006 2:57 am    Post subject: Re: How many of you understand a scopes "subtend" Reply with quote

Cool I think that it would be a "Great" article. I have been doing some work with several of my scopes to find just the thing that you are talking about. It seems that no two are the same unless they are identical mfg & size. If you would like some input for the article krop me a PM. All the best. Cool
Back to top
View user's profile Photo Gallery
Display posts from previous:   
Post new topic   Reply to topic   Printer Friendly Page    Forum Index » Gun & Firearm Discussions
Page 1 of 1
All times are GMT - 7 Hours



Jump to:  


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


Advertisements
 


Valid CSS! Valid HTML 4.01!
Click to check if this page is realy HTML 4.01 compliant for speed :)

All logos and trademarks in this site are property of HuntingNut.com.
The comments are property of their posters, all the rest © 2011 by HuntingNut.com
Interactive software released under GNU GPL, Code Credits, Privacy Policy

.: Upgraded to DragonFly 9.2 by Dizfunkshunal :.