Friday, March 22, 2013

Making a new front sight for a handi rifle in 30-30: or : 3 lbs of scraps for 1 lb of product

     Many experienced hunters and shooters can tell you there is not much to be desired over a quality single shot rifle. Accuracy, simplicity, reliability and versatility give this class of rifles a marked advantage over their more complex brethren. The NEF/H&R handi rifle has been an American favorite for these attributes for a while, yes they take some work to get them to really perform but there is little left to be desired for somebody on a budget. The best part of this line is the barrels swap out in a matter of seconds. These barrels are difficult to come by on the used market by themselves because they are favored by those frugal and utilitarian folks who have the host guns these go to and wish to get the most bang for their buck. Generally if you want additional barrels you must send your rifle into the company along with a check and they will fit what you want to your rifle. These set ups are wonderful if you can hunt deer in your area with a center-fire rifle and you are simply after putting meat on the table and not owning the newest and most advertised rifle/caliber/gear type stuff.  The single shot attribute is great for beginners and handloaders in a lot of ways. For a while I have been looking for a 30-30 rifle either a Marlin or Winchester lever action or a handi rifle. A few months ago my patience paid off and I purchased a 30-30 barrel for a NEF/H&R handi rifle for $90. The barrel came with a scope mount (no rear sight) and a front blade sight. Right away I ordered a Williams guide sight for the rear, after the first range trip with some handloads I noticed right away the rifle shot 3' high at 50 yards...VERY short front sight. This 30-30 needed some work before it would give me what I wanted out of it.

 I was told by a few people that the SB1 frame (mostly used for the shotgun frames) could be used in lieu of the SB2 (rifle frame, 30/06 .308 etc..) when using barrels for either the .357 magnum or the .30-30. From what I can discern these two chamberings along with perhaps a few others (.22 hornet?)  were offered on the SB1 frames before they were SB1 frames but I'm not going to make a sworn statement to that. The NEF/H&R single shot rifle and shotgun line has gone through lots of models but they have all pretty much been the same gun. Its just luck of the draw when buying spare barrels if they will fit your given receiver, you have to know how to check to make sure it is safe before firing. I will not get into how this is done just yet here, I need to get on about the front sight I made to get this rifle back on its feet.

The stock sight blade was much too short with the new rear sight it was obvious a taller front sight was needed in order to raise the point of impact. I tossed the idea around in my head for sometime and figured that with the 30-30 a wide range of bullet weights are used so having a front sight adjustable for elevation would work very well paired with my fully adjustable rear. I thought to myself "what is adjustable and easy to make".....AR-15 front sights of course!!!!!!! In this case I was going to be using A1 front sights since I like those much more than the A2 and I have a bunch of them in my parts box. For starters the A1 sight is threaded 8-36, which is a non standard tap...not hard to if you know where to look, don't go to lowes or menards thinking you'll find wont, you'll just find 8-32 and get frustrated. The 8-36 tap needs a #29 drill bit as well, again not something super easy to come up with.  I started with a block of 6061 aluminum MUCH too big for what I needed, I should have known better but since I was prototyping kinda I let it slide. After I measured the barrel I found a tapered reamer that would work for final fitting of the block to the barrel. This was CLOSE , about a 80% contact fit, a few light taps of the hammer gets it very close to 100% front to back. 

This side view shows the sight slipped on the barrel, its about twice as long as it needs to be but that give me some room for error.

You can see here just how oversized I made the blank, its better to start out with too much material when prototyping than too little sometimes but this may be excessive.
I decided to make the base with sight protectors as the thin posts on the A1 sight can bend easily if abused, not to mention its a bit of a snag point, protectors help avoid those issues. Not to mention the final product kind of looks like the front sight to a No4 Mk1 Enfield. I had to shorten up the threaded portion on the sight post considerably as well as the plunger needed to index the sight. The spring was shortened in half as well. The spacing of the plunger hole and the front sight post holes is somewhere around .206" from their respective centers, The recess for the sight is dead on 3/8". This recess needs to be a square bottom hole, I used a bottom cutting 3/8's end mill to do this. You could use a standard drill bit I guess but I'm not sure how that would turn out.

Here you can see the holes for the plunger and the sight at the bottom of the sight channel created by the sight protectors. Note, if you look close you can see the step from 3/8" to 1/2" when I was trying to decide what I liked better.

Yeeeah.....a lot of wasted time more time spent planning might prevent this.
The sight channel (the part you look down through) I made just under 3/4", I started out at 3/8" (which is roughly what the channel is on the AR-15) and quickly decided it needed to be wider. I went to 1/2" and it still needed to be wider. Since the sight block is out of aluminum the protectors needed to remain somewhat thick. I think where I ended up will prove to be a good balance of protection and field of view when looking through the rear peep sight. For the floor of the sight channel I also counter milled the front of it to reduce glare. This is caused from the fact I would be looking down onto a square surface when sighting down the rifle, its not a major thing but it helps when refining the sight quality.

Sight as seen looking down the barrel.
New front sight, Not a world class job but its a good first attempt. I could lighten it up a bit more but not by much . This slip over barrel design does tend to be a little blocky but it does have its advantages.

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