Swing-Lock .416 rifle

[swinglock]

This is just a heads-up letting everyone know that the newest Swing-Lock .416 cal. Long Range Rifle is now posted on the web site " swinglock.net ". Any questions or comments are appreciated.

Thanks,
Tom

[edge]

Sounds like a great rifle, and very purdy too.

I do think that RM is very optimistic with their ballistic coefficients.
I suspect that they are calculated from their shape vs from their actual drops

edge.

[bigmoose]

Now thats a big boomer, with the exception of the recoil pad, its a fine looking rifle, wish I was 10 years younger, [for a lot of reasons]
Makes my Buster bullet sound like a rim fire load.

Tom,
How much is the powder charge, and what powder is it.
Good Luck its a beauty.

Marty

[bigmoose]

Just went back to your site, and found the answers I was looking for.

[jeremylong]

after looking at that, it just reminds me how aggrevating the state of illinois is requiring a 45 cal mz for deer hunting.
Of course though the beast above may be quite fun in just straight long range competition.

[swinglock]

Thanks Edge. Yes that .923 B.C. for the 450 gr RM bullet is very high. Last week I was talking with George at RM and he said at 2750 fps it would be more like .880. Hornady also just came out with a .416 cal. 450 gr match bullet which supposedly has a B.C. of .720. I have some on order. Either way the B.C's are very good even if a bit inflated .

[marku]

Illinois has a .44 cal min which is actually a .429

[Richard]

Tom.................Am I missing something here? I went to the web-site and looked at the rifle.........VERY nice but then looked at the target................a 1.21" three shot group CTC at 118 yards? Is that a mis print? A Savage/Pac-Nor .45 will do that all day long? and better! Could it be you have the yardage wrong?
Richard

[swinglock]

Richard,

You gotta look closer at the target! There are two distinct clusters on that paper which represent accuracy as affected by ( 2 ) different size orifices.

The 1.21 group was shot using a .047 dia. orifice.

Look to the right and you will see another group which measures only .48 In.. That group was shot using a .042 dia. orifice.

The target was posted for two reasons. One was to show how orifice size can affect accuracy. The other of greatest importance was to show the potential accuracy of the rifle which is very good with the right orifice.

Other targets will be posted in the future.

Tom

[dannoboone]

Hi Tom. Do you make an open thumbover stock for us "lefties"?

Have you checked pressures on your rifles that you are getting
with the loads you are using?

[jeremylong]

MarkU - Almost lol!

There is allot going on with those swinglocks and allot around the ignition.

That orifice size just seems big, but thats allot of powder sitting in front of it too.

[marku]

Ive actually called and complained to DNR about the .429 min. So ill have to stick to the 325gr Parker Match Hunter

[swinglock]

Bigmoose,

Glad you like the rifle. On the Rucker recoil reducer, many don't like the appearance but it does aid in reducing recoil. I consider for some it will be a non-necessity since the muzzle brake is really very affective by itself. I have a few other more conventional profile light weight .416s currently being made which have standard pads and are featuring some very fancy walnut stocks with exotic fancy wood tips and caps. Real eye catchers! And still quite high performance with all bullets including the 450 gr ones mentioned. They will be posted as well with a big heads-up.

Richard,

Glad you think the rifle looks VERY nice. Thanks!

Dannoboone,

Yes, all stock patterns are available in left hand including the thumbover. In fact, at present I am near finished with another .416 which is almost identical to the gray rifle except that it is left handed and has a rosewood pattern stock.

On load pressure, I always do pressure traces during load development and maximum loads are held between 60 to 65 Kpsi. When developing loads, it is not only the pressure traces that get attention but everything is closely watched and contributes to establishing load limits.

Jeremy,

The orifice in this rifle is large as compared with orifices we are used to hearing about. Likely as you say because the powder chamber volume is quite large so other factors required for efficient ignition must also be increased.

Standard 209 primers were initially tested and found to be very unreliable. So, the preloaded priming module was developed which has so far proven to be very efficient, clean, reliable and quite easy to use.

Well, I need to get going.

Tom

[bigmoose]

Tom,
My 2 cents, your rifles are works of art.

[Deleted]

Yes and having laid hands on one several times they are even more impressive in the hands

[chuck41]

Beautiful workmanship, but a 450gr bullet at 2750fps is just way too much for me. I already have gross overkill with a 200gr bullet at that speed. The 6.5mm shooting a 120gr bullet at 3400fps sounds more to my personal liking, but still vastly overpowered for my needs.

[Richard]

Tom...........thanks for responding! I figured I missed something
Richard

[swinglock]

Thanks Chuck! But, one thing to consider is that those loads you mention are really maximum and nothing says you have to use them. That 450 gr bullet is the one you would use if you wanted to shoot half a mile or more. In the .416 you can also shoot 300 gr bullets and even lighten the load for those especially using the full formed bullets which don't need lots of pressure to obturate. Same goes for the 6.5mm. There are some nice shooting light loads for that which can be worked up. Of course, the rifle shown is one that only someone who wants to do lots of long range shooting would buy. In any case, a rifle can be built which best suits the type of shooting and conditions the customer has need for.

Tom

[edge]

Is there a stop that prevents the bullet from entering the chamber, or just a dedicated ramrod that is too short to allow that?

With less than full powder loads have you had any ignition problems, or is the chamber fairly small and it is always full?

edge.

[Richard]

Excellent question Edge!
Richard

[Jon]

If the powder does not fill the chamber how close to full does it have to be before it creates a problem?
Jon

[swinglock]

Edge,

The bullet comes to a positive stop against a hollow component I call a throat bushing so there is no way a bullet can drop into the chamber even with a reduced load.

None of the loads are compressed or 100% density.

There have been no ignition problems with this design even using reduced loads.


Jon,

The degree to which the chamber is filled depends upon which powder is being used. Even maximum loads do not totally fill the chamber in this particular design. So, I suppose one answer to your question would be that a problem is created when the rifle is loaded beyond specified limits and the degree to which the chamber is filled is not really the concern. Or, to come at this from a different angle lets say enough powder is loaded such that the chamber is over filled and powder extends into the barrel bore. Then, the bullet would not come to a solid stop against the throat bushing and seating of the bullet would not have a solid feel but rather feel cushioned. In that case, an obvious overload problem is indicated unless the design and load development allows for that condition.

Tom

[edge]

I like that design.

What powders have you had good success with and with your minimum load what percentage would you say the chamber is filled...if you don't mind sharing

In the past we have discussed ways of having an air space over the powder in an effort to reduce pressures. Your design seems pretty much foolproof which for the smaller calibers becomes very important!

edge.

[swinglock]

Edge,

Powders I have tested are all slow burners such as IMR or H4831, IMR 7828, H1000, Reloder 25, Retumbo, H50BMG and US869. In general good results have been obtained but for the time being, Retumbo is in the lead.

For a minimum load, that would depend upon how " minimum " the shooter might want to go. For the slower burning powders, it would not be recommended to reduce the load too much. For greatly reduced performance loads, faster burning powders would be tested and a powder even as fast as say SR4759 or AA5744 might be tried since they have good bulk. Even for reduced loads, pressure tracing would be included as part of the development since a " reduced " load can still have significant pressure. The percentage of chamber fill would depend upon the powder used and degree of performance reduction. One concern where the powder charge is reduced too much in volume is that shot to shot uniformity might become a problem so it is always better to work towards a good balance between uniformity as relates to chamber fill and the performance level being sought.

[Richard]

Tom..........I guess I'm picking your brain ;D but this "bullet stop"..........I am envisioning a "ring" so to speak, which is press fit into the powder chamber that is just somewhat smaller in diameter than the bore? Maybe even something that is tapered on the inside to mimic the shoulder in a CF cartridge?
Richard

[Richard]

After the above post I went to your site and began reading about how the rifle is constructed (should have done that before asking the question )
SEE.............that is why new members to this board need to read and re-read the HINTS AND TIPS section. Many question will be answered right there.
Anyway, it appears to me that this "module" must be some type of pre-machined "chamber" that is installed into the barrel. In my mind, I am picturing a piece of precisely machined round stock that a chambering "type" reamer is run in. The breech of the barrel is counter bored to accept this pre-machined chamber. Whether press fitted or glued in. Or maybe held in place by the breech plug? If I got this right? It is one heck of a set up!
Again, nice set up Tom!
By the way, I saw the picture of Bill Shehane in your Testimonials? Fat Boy! You should see him now He lost about 200 lbs. ( I shoot 1K with him and have one of his stocks)
Richard

[swinglock]

Richard,

The precision machined, soft steel orifice seal module has a solid base into which the orifice is installed. Forward of the base, it is a hollow, thin walled cylinder which is a press fit in the rear of the powder chamber when the breech plug is installed. The seal module functions in much the same way as a cartridge case except that it is a press fit which produces an automatic perfect seal. In the 6.5mm, .416 and other most current rifles, the seal module is also machined with a fine thread on its rear diameter. The purpose of that thread is to provide an easy means to PULL the seal from the REAR of the breech. The seal can also be knocked out of the breech from the muzzle using a good stiff metal rod but pulling the seal out with a very simple tool is much easier especially if the need arises to remove a charge due to a misfire.

The throat bushing completes the leading end of the powder chamber and is also very close tolerance machined for a press fit into both the front of the powder chamber and the rear, throat end of the barrel. It is a hollow cylinder with a large and small diameter separated by a flange. The flange is captured inside an exact fitting counterbore when the barrel is screwed into the breech and serves to lock the bushing on location. The hole through the throat bushing is slightly smaller than the barrels bore diameter which assures that a bullet will come to a positive stop when loaded and have no chance of dropping into the powder chamber.

I considered at least several different bushing/bullet stop designs with two that work well and are currently patent pending.

If you were to view a section through the length of the powder chamber it looks much the same as a bottle neck cartridge.

Glad to hear Bill has lost some weight assuming it is to the betterment of his health!

Tom

[Richard]

Tom...........Thank you for your detailed description.
Bill was at the Hickory NC Egg Shoot April 2, pushing his stocks...........(the first time I missed it in 11 years) and a friend of mine saw him there and did not recognize him at first? I don't know for a fact, but I would suspect he got a rude awakening from his cardiologist.
Richard