[papasan]

howdy.

I bought a TFO set (TG131GT1) for my Glock 19 just for the front sight. it's currently mounted with an AmeriGlo rear (GL-405L), I like the setup but unfortunately the rear sight is too low (or front sight is too high) and the gun is shooting low if I line it up properly.

anyone with experience or have a caliper and a set of the TFO sights mounted that could measure the rears? would a GL-406L be a better match or do I need to go even higher? there doesn't seem to be much info about using the TFO fronts with different rears, either that or my Google-fu sucks this morning.

I'm tempted to just ditch the setup and go with a packaged set like the Hacks or Defoor but would be nice to get this TFO frankenstein working.

thanks.

[Breadman03]

I take it when you aim at the bull, your rounds are impacting low.

Did you shoot this gun to POA before the sight change? If yes, tell us how far away the target was and how low you were shooting. I saw a formula to calculate sight height on another forum. I'll see if I can find it.

[Breadman03]

Here is the post, quoted from MarlinOwners.com:

Originally Posted by timski

Front Sight Height Calculator


Frequently a change in the rear sight of a rifle means a taller or shorter front sight is desired. Determining the desired height is a simple calculation that is explained below.

1.Shoot a group (at least three shots) with the current front sight. This can be done from any known distance. Convert the range to inches. (i.e. 100 yards is 36X100 or 3600 inches)

2.Measure the distance the center of the group is from the desired point of impact in inches.

3.Measure the distance from the front sight to the rear sight in inches. This is called the sight radius.

4.The change in height needed is calculated by multiplying the desired change from step 2 by the sight radius in step 3 and dividing by the range (in inches) that the group was fired at from step 1.

For example:

Let's say our rifle shot 10 inches high at 100 yards and the sight radius of our rifle is 23 inches. We can calculate the amount of change we need in the front sight as follows:

Change = 10 inches X 23 inches = .064 inches or about 1/16 of an inch.
3600 inches

Now to order a front sight the correct height, You measure the height of the front sight on your rifle from the bottom of the dovetail to the top of the sight, add the change calculated above and ask for that height. Use a caliper or micrometer to measure with since you need to have an answer in thousands of an inch.

It is important to note that front sights adjust the opposite direction you want to move the point of impact. In the example above we were shooting high so we needed a taller front sight. If we were shooting low we would want a shorter front sight.

Rear sights adjust in the direction we want the move the point of impact. If we want to move the point of impact to the left we move the rear sight to the left.

I'm subscribed to this thread, so just post up your info and I can give you a hand with the calculations.

[papasan]

well, that's pretty interesting. I have a few pics archived from my cell phone, will need to dig them out and see if I can figure it out.

still, would be interesting to know what the technical/theoretical 25y zero rear is for the TFO front. as I'm a fairly new shooter, not yet 100% confident in my ability, if I figured it out this way there maybe some lingering doubt if I'm still not shooting bulls after a swap.

another forum suggested this tool, similar results I would imagine...
http://www.ameriglo.net/sights/calculator

[D.R.D.]

TFO = .195 high front sight (measured from top of slide to the top of the sight), needs at least .286 - .294 rear total height (measured from the bottom of the dovetail to the top of the sight shoulders).

I got a .272 high http://www.ameriglo.net/sites/defaul...s/gl405pra.jpg (Ameriglo 406 PRA), so I'm .015 low, and I've been shooting a few inches low at 25 yards. (Previously at 6" groups at 25 yards with TFOs front & rear). I tested at 3 - 10 yards and it was consistently a little low there too. You are shooting the GL-205L which is .256 high. That puts you low at a difference of .030 That's double my deficit, so I can imagine you'd be hitting quite low (given your grip, stance, distance, and ammo load have been consistent).

The only Ameriglos that would truly work with the TFO front are: (All are .287 high, but only .150 wide)
http://www.ameriglo.net/sites/defaul...ies%20lime.jpg - Rear of the CAPS set
http://www.southernpoliceequipment.c...b&b=26&id=1317 - GTR-730
http://www.southernpoliceequipment.c...b&b=26&id=1328 - GL-402 (discontinued)

Love the TFO, but it has come lose, even with loctite (blue) and I'm seriously considering whether or not the fiber optic bonus will really come in all that helpful for my needs. If I found myself doing more outdoor competition stuff, It would rock. But as an indoor defensive handgun set-up for low light, it's really the wider .180 rear notch that allows easy and fast front sight acquisition from the silhouette of a tac-light that is key. Under those conditions, I've tested and tested, and it's the very rare light condition that I can even make use of the tritium. It's all about the sight picture, sights silhouetted by your light source, and consistent weapon presentation (especially for home defense & CQB).

That brings up a point though,...will a .015 low rear sight really matter that much at close distances? Probably not. But, given that under stress, the best you can hope for is the worst you do in training, I'd want my weapon system to be as dialed-in as possible leaving the very least room for mechanical error (that's why we have Glock's in the first place, no?).

The TFO front has great features, but the rear, I find too busy and the notch too narrow for my liking.
Ameriglo, Warren, Trij, all make great "u" type notches for faster targeting.
It's just been a tough search to find a set-up that does it all.
Even using a Trijicon RMR would have its drawbacks.

I'm considering switching it all out to this: (Ameriglo GL-301 or 304 Green/Lime Green front & green or yellow rear) ProGlo-iDot
http://www.cheaperthandirt.com/product/2-AMGGL-301
http://www.pistolaccents.com/assets/..._dot_glock.jpg
http://glocktalk.com/forums/showthread.php?t=1419675
http://i20.photobucket.com/albums/b2...516-00026a.jpg
http://jerkingthetrigger.com/blog/20...glo-i-dot-pro/

This set up seems like it would offer:
1. Fast target acquisition with a larger rear notch
2. Clear silhouette of the sight picture when using a tac-light at night
3. Brightly colored front sight for daylight conditions, or when shooting against a darker-colored target
4. Tritium just in case the twilight conditions are present
5. "Straight-8" type dot sighting for vertical alignment if needed

Too bad Ameriglo doesn't do the Tritium-Fiber-Optic combo. Probably a patent issue.

[D.R.D.]

Another plus for Ameriglo is the flat front face of the rear site that lends itself to easily running single hand racking and clearing manipulations off your belt, holster, or a table. Rear sights with slants (Heinie, Warren, Truglo, Novak) make that much more difficult. In fact Rob Pincus just designed a new rear sight with Ameriglo for that very purpose called the "Claw" http://clawrearsight.com/

[D.R.D.]

I'm not sure if this will be viewable, but is what my set up looks like now:
https://mail-attachment.googleuserco...Qvc9ODEKjaD97g

[papasan]

Originally Posted by D.R.D.

I'm not sure if this will be viewable, but is what my set up looks like now:
https://mail-attachment.googleuserco...Qvc9ODEKjaD97g

link is't working.


so I got tired of playing the guessing game and decided to get another AmeriGlo front that would match the rear. went with the CAP green/green front. on a related note I have a set of Glock low TFOs for sale (; here's a pic for size comparison...

[D.R.D.]

Wow, that CAPS sight pops out! Nicely done.

[papasan]

in reduced and low/no light the CAP does seem quicker. in full light the fiber is impossible to beat though, it glows like an angry eye.

[D.R.D.]

Awesome article if you haven't already read it:
http://www.handgunsmag.com/2010/09/2...ativep_061207/

[papasan]

awesome, thanks!

[D.R.D.]

Here's where I am now in daylight (focus on front sight):


In low light with tac light on (focus on threat/lighted area):
http://i.imgur.com/P6MhO.jpg

This is on the way:
http://www.arotek.com/default.aspx?p...tView&Part=124
I'm gonna try it out, and paint the surrounding portion of the front TFO face with day-glow green nail-polish.

If that doesn't work then I'll do this:
Ameriglo GL-304 (Green/Lime Green tritium ProGlo front, with yellow tritium iDot rear)
http://www.cheaperthandirt.com/product/2-AMGGL-301

I'll post pics along as it progresses.

[D.R.D.]

Here is the painted TFO with green nail polish - we'll see if it stays on.
(rear site focus):

(front site focus):

The front site is actually brighter in daylight, plus the fiber optic shines in the middle. It wasn't easy to capture it with the camera (plus it was against a white/neutral background). With overhead / ambient light, you can't miss it. Kinda like the CAPS. Plus, it also is fiber optic, and tritium for twilight acquisition. We'll see if it still shoots low with the aro-tek 'ghost' ring (not actually a ghost ring, more like the hexsite).

[D.R.D.]

Here is the front Truglo TFO with the Aro-tek ring rear (http://www.arotek.com/default.aspx?p...tView&Part=124)

The face around the tritium fiber-optic is painted with day-glow green nail polish and a clear sealant. The top of the fiber optic is secured with clear loctite epoxy.



Front sight focus (florescent light indoors):

Target-focus indoors:


Front sight focus (daylight):

Target-focus (daylight):


Close to what it will actually look like with target focus, awoken in the middle of night, without glasses or contacts on, shaky, with a x200A beam:

[D.R.D.]

Side view - incredibly easy to do one hand racking manipulations off of any surface with such a high rear ring. Plus, it's rounded and won't snag on anything, and still fit in any holster...and requires no batteries.


Range report to come...
(if the front sight doesn't work, I'll scrap the TFO all together and put this on (painted green too, of course ;-)
http://www.arotek.com/default.aspx?p...tView&Part=205

...and if that isn't the ticket, then I'll just go back to the original idea of:
Ameriglo GL-304 (Green/Lime Green tritium ProGlo front, with yellow tritium iDot rear)
http://www.cheaperthandirt.com/product/2-AMGGL-301