Gunsmithing Single point or pilot tap i guess

[holy cow]

Can someone direct me to some reading on these 2 on the pros and cons. I see that most all use the single point method to true up an action. Are their any pros or cons to having 1 the other way done.

Thanks,
Dan

 

[hero's machine]

Re: Single point or pilot tap i guess

If the hole was not dead nuts to start with, a tap just means you have fresh threads that are not 100% still. If it is single pointed.....and indicated correctly, you are back to square.

 

[wnroscoe]

Re: Single point or pilot tap i guess

Single point cuts true and is the prefered method. A tap just follows whats already there.

 

[hntbambi]

Re: Single point or pilot tap i guess

I have done 4 of them with a piloted tap that shoot great. I would love to see some metrics from gunsmiths <span style="font-style: italic">showing proof</span> that the groups are smaller from single point cuts.

 

[my human host]

Re: Single point or pilot tap i guess

There was a thread on this not too long ago. You might try searching for it.

I started out using the Manson tools. I did build some pretty accurate rifles with them, used in conjuction with my lathe. The reason I bought them is that my first lathe was a wore out POS and would have made matters worse rather than better.

The last couple years I've been running the actions I did with the Manson tools through my new lathe and single pointing them. Typically, what I find is that the action face and locking lug abutments are close to dead nuts on and the threads are still out three to five thou.

Keep in mind that many people comission a build with well respected smiths because of the attention to detail they're known for. Some of this is quality for the sake of quality and may or may not make a measurable difference on target. Myself, I won't be going back to the tap setup. The tap system is much faster though. I certainly wouldn't badmouth a smith for using it as long as the savings are passed on to the customer.

Doing a conclusive study on this subject would be horribly expensive and time consuming. Maybe if a person did a hundred guns each way, you'd get some meaningful data. I want to say one of the most experienced men in this reguard was Mr. Tooley. I'm not 100 percent on that though. Like I said you may want to seek out the older threads.

 

[jake6547]

Re: Single point or pilot tap i guess

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: wnroscoe</div><div class="ubbcode-body">Single point cuts true and is the prefered method. A tap just follows whats already there. </div></div>
X2 from a machinest's perspective he's 100% correct.

 

[wnroscoe]

Re: Single point or pilot tap i guess

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Hntbambi</div><div class="ubbcode-body">I have done 4 of them with a piloted tap that shoot great. I would love to see some metrics from gunsmiths <span style="font-style: italic">showing proof</span> that the groups are smaller from single point cuts. </div></div>

Do you really think that the piloted taps and reamers used for receiver truing will cut parallel, concentric and perpendicular to the receiver raceway?

I’ve tried both methods and to be completely honest, the hand tool method works quite well but, it bothered me every time I used the hand tools knowing I had a lathe sitting there with fixtures and tooling to employ the single point method. Can you dial a part in to .0002” or under while using hand tools? I sure cant but, I can in the lathe.

If you were paying me to build your rifle would you want me to use the single point method or hand tools? I use the single point method on my personal rifles and offer a .250 moa accuracy guarantee on rifles I build, just for conversation.

The reamers that also face the receiver are prone to chatter on the face and lug abutments. The single point method leaves a mirror like surface finish on the part with no chatter.

Bottom line is this, no matter the method, the center line of the bolt body, receiver raceway, receiver threads, barrel threads, chamber and throat must all be aligned as close to zero as possible in order to achieve the highest level of accuracy possible. Excessive run out in one of these areas will degrade accuracy, two or more areas, you have a tolerance stacking issue and the wheels on your accuracy vehicle will come off.

Those that can, do.

Single point method = Pros

 

[x ring accuracy]

Re: Single point or pilot tap i guess

We can and do, but tell us how you really feel, : )

 

[STR]

Re: Single point or pilot tap i guess

Very well said by William Roscoe, as usual. I too agree with single point cut for truing. A lot of factory rifles shoot pretty good, but we aren't after pretty good when we pay big hard earned dollars for a custom built. We are after 1/4 MOA, one small ragged hole, you know, the best. That's the kind of results you will always get when properly done single point truing is used. If the piloted system really worked so good, why is it that none of the pros use it??????

 

[Keith Johns]

Re: Single point or pilot tap i guess

Single point truing the threads DOES produce straighter/squarer threads.
The tap cleans them up and trues them a little, but I don't know how much.

Both methods build a rifle capable of shooting one hole. Its ALL on the smith doing the machining.

They both have pros and cons... Single pointing has fewer cons though

 

[angelballer]

Re: Single point or pilot tap i guess

What cons does single point have other than needing a lathe?

 

[my human host]

Re: Single point or pilot tap i guess

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: angelballer</div><div class="ubbcode-body">What cons does single point have other than needing a lathe? </div></div>
None. But if you're not a trained machinist, you may need a clean pair of Scooby Doo's after the first time you chase internal threads.

 

[Keith Johns]

Re: Single point or pilot tap i guess

None other than time, the possibility of threads that are the wrong angle because of threading tool set up, and the extra liability(cant screw up obviously).


Single point is better. Both build 1/4" rifles.

 

[angelballer]

Re: Single point or pilot tap i guess

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Keith at PCR</div><div class="ubbcode-body">None other than time, the possibility of threads that are the wrong angle because of threading tool set up, and the extra liability(cant screw up obviously).


Single point is better. Both build 1/4" rifles.</div></div>

I would think a professional gunsmith should be able to chase internal threads and know how to setup a threading tool though.

Also, you say both build 1/4" rifles. I think that would depend on the receiver's tolerances with the tap method. If the threads are way out, the tap will just make them bigger while the single point method will actually fix them. If you are using a tap, how do you know if the threads are just slightly off or not? It seems pretty easy with the single point method.

 

[Ballistic Artist]

Re: Single point or pilot tap i guess

If you're charging a customer to true up an action you better use single point on the threads. Word gets out that you use a tap and buisiness will get bad quickly.

 

[eddief]

Re: Single point or pilot tap i guess

Both methods work and work well. With that being said, when single pointed correctly, you are then able to get a VERY nice thread fit between receiver and barrel tennon.

Do I want to single point with a 1.5 lb. tool or my 2800 lb lathe?

Rigidity is where it's at and I prefer my lathe+single point method.

 

[LRI]

Re: Single point or pilot tap i guess

Anyone here ever own or mess with a tube amp for home audio?

I own one. A Manley Labs "stingray". I bought it cause at the time I could and I've always wanted an analog setup for playing vinyl. I caught the bug from my ol man.

Point is any quality transistor based amp is far more efficient, has more power, and is available for almost pennies on the dollar of what a quality tube amp goes for.

Yet tube amps are almost worshiped with it comes to class A home audio.

Much is the same in gunmaking. Taps are far faster, cheaper to use, and may very well produce a rifle just as capable as one that's been "jerked off" for 3 hours on a lathe (or in my case MILL). As an interest of personal pride many smiths can't bring themselves to use one for accurizing a receiver. For those that "get it" there's very little reaching to understand what I'm saying. For those that "don't" do whatever suits you.

IT really is that simple.

C.

PS: Here's what ours look like:

Footnote:

We barrel alot of receivers here. ALOT. They come from everywhere in all shapes and sizes. We've seen threads that fit nice and some that I would consider unsafe to the shooter. One in particular was double tracked due to a bad insert and was -.04" (wholly crap!) undersize. It was chambered in 7mm RSAUM. The owner said the rifle shot phenomenally well. Since we know the guy and know that he shoots a great deal I have to take him at his word.

It begs the question. Just how important is it? I try to edge to caution so we'll continue to do ours as we do. If for no other reason than it serves as a marketing tool. However when I see sloppy threads on rifles that shoot right along side anything else its tough to ignore.

 

[Wade]

Re: Single point or pilot tap i guess

I would imagine that most accomplished gunsmiths have spent a fair amount of time checking their work in ways other than test firing.

The barrel that is in the lathe and is being threaded and chambered for said receiver. With the thread depth just enough to thread the reciever on tight the rear of the bolt raceway can be indicated to show concentricity of threads. The same can be done once the work is complete but should only show squareness of reciever face if the receiver threads are somewhat straight and some thread clearance is allowed. The same can be done to check straightness of custom actions.

Obviously single point is better from a theoretical standpoint.(straighter). But is it enough to matter? You would probably be surprised at who trues 700s using the piloted tap method.

 

[sixtwoeightyfour]

Re: Single point or pilot tap i guess

First off I am not a gunsmith, I am a machinest that makes my own rifles. I personally dont understand why the threads are such a big deal anyway, my first thought is that as long as all surfaces are parallel (bolt face, bolt abutment in action and action face) and that barrel tennon shoulder is perpindicular to chamber and bore. and threads have enough "give" to allow action and barrel shoulder to snug parallel it shouldn't really matter how far "out" threads are except for possible not allowing firing pin to hit center of cartridge. Again I am not a gunsmith so you guys that do alot of gunwork please help me wrap my brain around this



BTW: I single point all my threads now just to make them purdy.

 

[hero's machine]

Re: Single point or pilot tap i guess

I feel its more of an effort to gain 100% consistent thread engagement, which makes consistency an attainable goal. Threads will self align and if faces are square and offering solid bearing, ailignment is not the issue, bit think of the harmonics going on. Having some actions get more solid thread contact than others is another variable that can be reduced in an effort to create the best possible work.

 

[2156SMK]

Re: Single point or pilot tap i guess

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Wade</div><div class="ubbcode-body">You would probably be surprised at who trues 700s using the piloted tap method.</div></div>

You sure won't see those companies bragging about it.

 

[wnroscoe]

Re: Single point or pilot tap i guess

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Wade</div><div class="ubbcode-body">You would probably be surprised at who trues 700s using the piloted tap method.</div></div>

I wouldn’t be surprised. Those same companies chamber between centers and in a steady rest as well.