44 Mag Throat Diameter

[Mal Paso]

S&W has been cutting the late model cylinder throats tight to boost jacketed performance. The actual SAAMI Spec is .4325 but all the late model 629s I've seen are .428"-.4285". I only shoot lead and fit is a lot more important. I bought the Manson Reamer and opened my 629 throats to .4313" and size bullets .431"+ to match over a .429" groove. After about 200 rounds a couple passes with a stiff bronze brush will knock out a few sparkles of lead powder but that's it. The real surprise was how much better specials shoot. I'm hitting 100m Rams with Specials now (no Mags allowed).

The slight tooling left by the reamer is not an issue. Alignment and constant diameter is more important than perfectly smooth. Polishing will open up throats too but more equipment is required.

 

[Sven]

Dan,

It's been several years ago, but I have used the services of the "Cylindersmith". I don't remember the actual numbers, anymore, but I know my 629-4 MG had cylinder throats that measured less than the bore. I mainly shoot cast bullets sized to .431 or .432. I had my cylinder throats opened to .4305 (that I do remember), and get good accuracy with next to no leading at 1100 to 1200 fps.

 

[Mal Paso]

Cylindersmith only does 45 cal. now. At one time he offered 2 sizes of 44 cal throats. Manson made him a couple reamers in sizes not offered in the catalog.

 

[catfish_dan]

thanks for the additional info, I'm narrowing down a few shops in my area that can do the job. looking forward to getting this done once and for all. Thanks again.

 

[murf205]

Well, Dan, I just got my model 24 Classic back from the Customer Dis-service department amd they told me the same old song and dance--"it's within spec, no service required". Mine has .428 throats(as per pin guage), and it leads like the devil. On a good day it shoots about 4 1/2" @ 25 yds. I'm no pro, but I can do a bunch better than this 44 will shoot. You can bet you last $ this is my last new Smith. BTW, they test fired my gun but they neglected to send me a target--like I did for them to see.
Murf

 

[catfish_dan]

my saga still continues as far as getting the throats opened up. I was not able to find anyone in my area interested in opening the throats up so I ended up contacting S&W again. I asked what the charges would be to have them do the work and they estimated ~170$. I'm not comfortable doing this type of work myself so I asked if they could evaluate the piece, knowing full well they won't cover it, and then elect to pay them to do it. Yah, not my first choice but hopefully they can handle it.

That was 1 month ago, they said I would receive a shipping label to send in the piece. After several emails asking ***, I finally received the label and will be sending it in on Monday. They are definitely not the same S&W from years back. Live and learn. When I receive the piece back, I'll update how it went.

Dan

 

[jepp2]

I asked what the charges would be to have them do the work and they estimated ~170$.

Just curious why you chose to pay $170 rather than $75 at Bowan Classic? I personally would prefer to have Bowan hone them rather than have S&W do the work. The turnaround time will be substantially less also.


From the Bowan site link

No. SW230(*) Hone cylinder throats Undersize throats are adjusted, where indicated, to proper diameter to improve accuracy and minimize leading.

SW230 $75.00

 

[catfish_dan]

S&W pays the shipping to and from, and according to the Bowan site, the cost for Fedex next day air is 65$ so paying shipping both ways and then the cost of the service ends up costing more. Also, if the planets align and they actually agree to cover the cost of the mod then I end up paying nothing. I know this isn't gonna happen but worth a shot.

Thanks for the additional info though

 

[BLUEDOT37]

I believe you made the best choice, though I understand your reluctance. Hopefully you'll be peasantly surprised. (I'm sending my 657-5 back Monday too because the chambers are oversized causing case bulging.)

Previously I looked at the SAAMI specs for the 41Mag & I just looked at them for the 44Mag. As I read it, the chamber specs are "all dia. +.004" (not +/-), per the footnote under Chamber, from the .4325" chamber spec. (The groove dia. spec is .4290") These must be a carry-over from the "old days", just like the loose ones they show for the 45 Colt.

 

[jepp2]

S&W pays the shipping to and from, and according to the Bowan site, the cost for Fedex next day air is 65$

I hope S&W does cover the shipping and does the work for free. The shipping to Bowan would only be around $6. You only have to send them the cylinder, not the revolver. So you can ship it in a small USPS flat rate box.

 

[murf205]

Well, I finally had enough of S&W's bull spit and bought a Manson cylinder throat reamer and pilot pack. I taped the cylinder with masking tape to write on and numbered each cylinder. Then I used the pilots to see which one was a slip(non interference) fit and wrote the size on the masking tape corresponding to that cyl. Used pipe thread cutting oil and followed the instructions--piece of cake!! Clean the reamer BEFORE you pull it back through the cylinder and do'nt turn it backwards. Mild pressure is all that is needed. I chucked my reamer up in a drill chuck that was not mounted to a drill for a handle and it was perfect. Use plenty oil and go slow. Throats look great, and I'll shoot some loads and report. I called Manson and talked to Dave Manson when I ordered the reamer and he was a huge help. Super nice guy and he could'nt believe what S&W said when I told them that my throats were .4275-.428. Cost was $145 shipped UPS.
Murf205

 

[murf205]

Ok guys, here's my latest on cylinder throats, now that I have decided to forget about the dildoes at customer dis-service. I got the throating reamer from Dave Manson if 3 days. I bought the pilot pack because my 24 had 3 different dia. throats. Wow, no wonder it would'nt hit a bull in the backside. The smallest was [email protected], 3 were .428 and 1 was .4285. I chucked the reamer in a drill chuck not attached to a drill, but Manson sells a tee handle with a set screw that is perfect for the job. I used pipe thread cutting oil and very mild pressure on the reamer and the results were actually smoother than factory cut throats. Use masking tape to identify each cylinder hole and write the pilot size on the tape prior to starting. Check the pilots on a clean throat and look for a good snug NON interference fit. In other words, do'nt force it when your checking pilot fit. Put something under the cylinder to catch the oil and you are ready. Here are my results with a Lee cast boolit and w/gas check sized to .430. Murf

 

[murf205]

Here are Mansons reamer instructions. If you have drilled and tapped anything, you can do this. Just be carefull putting the reamer in past the chamber, but it self centers when the pilot slides in the throat hole.
Murf

 

[murf205]

Here they are.

 

[Boxhead]

I would buy some quality hand cast bullets as close to the original Keith design as possible from either Montana Bullet Works and Beartooth Bullets sized to .430" load it to 1100 fps or so (I like HS-6 when running the 44 there) and shoot. I suspect that the gun will shoot very, very well. That said, Cylindersmith does fine work.

 

[murf205]

So far this model 24 has not taken a shine to keith type bullets. The original Keith bullets are a pain to cast(I do'nt buy bullets anymore) because of the square bottom lube groove. Works fine when shooting but they are a bit harder to get to drop out of the mould. It's still a work in progress and I've been using a Lyman 429421 keith mould but I am going to order a custom 250 gr mould from Accurate Molds. The man who makes them does some of the most beautifull work You ever saw on a bullet mould. I've never tried HS-6, but a lot of people love it. I have 5lbs of Unique and of the 12 44's I've owned, I never had one that would'nt at least tolerate it or 2400. When I hit the right load, it usually is the bullet and/or the pressure that makes the diff.
Murf205

 

[murf205]

BTW, Boxhead, Cylindersmith does'nt do anything but .45 cylinders now. He told me that he is trying to get out of the business, so if ya got a .45 that needs opening up, better get it to him.
Murf205

 

[dla]

great info, thanks. I'm just waiting on a reply from S&W before I look to get the throats opened to .430. I emailed S&W asking why the throats are so close to being out of spec relative to SAAMI. In the SAAMI docs, the throat is listed as .4325 +/- .004 which leaves a throat of .428 just barely within. After a reply, I'll be looking to find someone reputable to do the honing.

I am so glad I found this forum because before this I never considered reviewing the specs on my gun. I thought my leading issues were a result of too soft lead. I even went so far as to start electroplating my cast rounds. Came out pretty good too, I was plating 50 rounds at a time with a nice hard shiny coating. I was shocked when I tested the rounds and they leaded horribly too. Live and learn

I might be wrong, but the SAAMI drawing for minimum chamber has a tolerance of +.004, not +/- .004.

Here is the SAAMI 44 mag drawing

But on another note, it isn't trivial to measure the bore of S&W's 5 grove/land system - not something I would try without a ring gauge set. And measuring the throat isn't something one can do accurately with a Harbor Freight expander and a +/.001" caliper.

My point here is that folks should get a pro to do the measurements before getting all excited about opening the throats.

I'd feel a whole lot more comfortable with this discussion if there was some hard data collection taking place. I.e. Ransom Rest BEFORE reaming and Ransom Rest AFTER reaming.

 

[catfish_dan]

yup, you're right + .004 so my throats, measured with precision gauge pins from the company I work for QA department are out of spec. I was also working with 2 ex-S&W mechanical engineers that happen to work with me. I live a town over from S&W so there are a few around. I'm pretty confident of the measurement.

As I stated in earlier posts, my issue is not with accuracy but severe leading. I couldn't get through half a box before the leading was so severe that the grooves were no longer visible in the barrel. So I guess that's pretty exciting.

Dan

 

[murf205]

dla, I do'nt use Harbor Freight anything and I DID check the throats with pin guages that I bought from Carr-Lane in St. Louis, Mo. As far as being a pro, pin guages do not require a genius to use as long as the throats are clean. As far as "getting all excited" I did'nt. I just opened the throats from .4275 to .430, which is a lot closer to where they should be and the results were obvious, to me at least. I do'nt own a Ransom rest-spent the money on a throating reamer.