Reamers, solid or floating pilot

[ratpatrol]

Do floating pilot chamber reamers really cut a more accurate chamber over a solid pilot reamer?
My Friend has chambered a lot of guns and mostly has Cly more solid pilot reamers, I said that's fine for hunting guns but no good for super accuracy. Can you see the difference on paper? Is it worth the extra cost? How tight do you fit the bushing to the bore? I would think a tight slip fit.
I said a solid pilot could damage the lands, Has anybody used a bore scope to check after cutting a new chamber?

 

[Rustystud]

Rapatrol:

You have several variables in your question. If the solid pilot reamer has a propper fit pilot diameter it would most likely give you the best chamber. Let me say more before I get jumped. Rarely will you get two barrels exactly the same bore diameter. This is true even from the same manufacture. They don't know ahead of time just how much lapping thay will have to do.

Piloted reamers can be ordered with a custom fit pilot. Most who order reamers just order the standard pilot diameter. You will find Dave Kiff at Pacific Tool and Gauge, Dave Manson at Dave Manson/Loon Lake, and the folks at Clymer all sell custom OD pilots in .0002 increments. I have about 25 different sized pilots for each caliber. All have about .001 clearance on the ID and are in .0002 size diffences in the OD.

The removable pilots serve a second function. They act as a bearing keeping the reamer from scoring the throat area of the chamber.

You have gunsmiths on both sides of the fence on this issue. My 2 cents worth is if you are using a flush system then a removable pilot is a no brainer.

Rustystud

 

[fdshuster]

Ratpatrol: I've always believed in floating pilot reamers, and bought them from JGS & Pacific: they are works of art. But a friend of mine recently cut a 22BR .251 neck chamber for me in a Shilen Stainless barrel, using his Clymer fixed pilot reamer. When I looked at his chambering with my borescope, I saw what I consider to be as close to a perfect chamber as is possible. Everything is symetrical, square, like an engineering drawing, and without a single mark on the lands and grooves from the fixed pilot. I still don't know how he did it. I believe both types can cut a high-quality chamber: depends on how much time the "operator" is willing to spend, and the degree of their skills.

 

[ratpatrol]

I'm just a home shop,backyard gun hobbyist,re barreled several Mauser actions on my own guns to learn the trade.I've done 223,22-250,6mm rem 308,35wheelen,all turned out excellent.
The project I'm doing now is a Savage 12vss target action,Keirger 8 t Paloma barrel,6br chamber,choate bench rest stock,I've rented a live pilot,Elk Ridge reamer.do here Monday.
Theards are cut for a no nut install to action. Barrel dialed in to less than .0001 run out.I plan on removing the bolt firings pin,leavening the extractor in bolt to head space,cut chamber on lathe .020 short,assemble and torque to 35 ft lbs,finish reaming to go head space.
Any help or advice ????
Looking for a 100yrd fly shooter............

 

[JDJones]

Ratpatrol, I personaly think that the solid pilot reamers can and do cut just as accurate as chamber as the floating pilot if the same care is taken when chambering and the reamer is made well. The floating reamers make the job a little easier and lower the risk of dinging the lands in the throat.

A bit of advice you said that your barrel is already dialed in, cut and ready to chamber I highly recomend that you recheck your barrel before you chamber it, its amazing how much metal can move even in a climate controled enviroment, I have seen barrels setup and left over night be as much as .002" off in the morning !!!

 

[butchlambert]

Listen to JD. Remember if you have a snug fitting bushing, it will score the rifling as it follows the bore. You need at least .0002 clearance for the bushing and you will find a built in .0002 between the bushing and reamer. As you know a reamer will follow the hole. What if you drill and bore first? If you have a short stiff boring bar, you can taper bore to within say .010 and have a hole that will indicate round. Now your reamer will follow the straight hole that you bored.Thats assuming you have a solid pilot or bushing that is loose in the bore. It will not allow it to follow a crooked barrel. Now throw rocks at me, but think about it first.
Butch

 

[TRECustom]

I haven't cut enough chambers to say for sure which is better. I like the idea of having removable pilots to fit any bore size variation, but most of my meager collection of reamers are Manson solid pilots. I once cut a .340 Wby chamber with an,expensive) Clymer ti-n coated, removable pilot reamer. Couldn't tell that it made a better or more centered chamber.

Bottom line for me is I'm more comfortable with solid pilot reamers. Be sure to use a spider on the back end of the spindle and indicate the barrel O.D. there to less than .005" t.i.r. I don't like hand finishing a chamber. Depending on the thread size, you ought to make up at around 100 ft/lbs. 35 ft/lbs is too light.

I have an old Hawkeye borescope and haven't seen scratches, but have seen what may be very light burnishing on the faces of the lands. However, I have seen shallow rings up on the shoulder of chambers.

I haven't barreled many rifles, and have never done a benchrest rifle, but I have a working gun that shoots 1/4 moa and another one that shot in the low teens. May be just luck. Terry Bradshaw once said that if he had a choice between real good or real lucky, he'd take real lucky every time!

I doubt if there is anyone out there who does things the same way, but I have read and watched and listened and this way works for me.

Good shooting, Tom

 

[3sixbits]

I had this same conversation with the late KEITH FRANCES many years ago, KEITH was one of the finest tool makers that ever made a chamber reamer. As I recall the conversation, I wondered why anybody would want to use a solid pilot reamer when they could use a bushed reamer. KEITH, replied he had no clue why either.

I do not think it is possible to cut a chamber and not have cross hatch marks in the throat, with either style reamer. That's why we polish the throats during break-in.

There is a law about reamers, by there vary nature they want to cut over. A solid pilot reamer has to fit in the vary smallest bore, It stands to reason if you put something that is guided into a larger hole than what the pilot is, it's going to cut over.

 

[TRECustom]

3sixbits, welcome to the site! I'm still new here myself.

As I said, I haven't done a benchrest gun, so I don't know how much more I would do. My very limited experience with chamber reamers though, is that they appear to naturally want to center themselves if the setup is close enough to let them. That is mostly based on watching reamers in a floating holder appear to hold absolutely still. Appearently the reamer stays true to the bore in spite of some runout in the setup. I have discovered that I can't see or feel even a full mil of runout. I'm totally dependent on the indicators.

I started using solid pilot reamers because they were cheaper and available, but stuck with them because they could be completely cleaned between passes and looked stiffer. I brush the big cuttings off first and then use low pressure compressed air to completely clean the reamer and chamber between passes.

I talked with Dave Manson about reaming speed, and cleanup interval. I asked him about solid vs removeable pilots, but it was too long ago for me to quote him, except that he makes both types.

I don't know enough to recommend either type, it's just turned out that my personal preference is the solid pilot.


This is a good thread, and I hope some 'smiths will weigh in.
Tom

 

[ratpatrol]

I have a old heavy barreled,FN action shot out 243 Win,pulled the barrel, cut a inch off, new threads and a 6mm Rem chamber,cut with a solid pilot reamer,the reamer was not very sharp, and close to finish depth it started to chatter,I let it run free,light pressure in lathe to clean up. I have never tried to cut to "go no-go" spec. on the lathe,you are saying to shoot for .001 short for thread stretch for a Mauser action.Anyway I had to finish up by hand and it chattered again,Any advise other that start over? I can feel it in fired brass,good thing is first three shots about .375 group.

My 6br Savage action project turn out excellent,10 brake in shots and cleaning,sight in and first group three shots .250 g.
31gr varget 95grvld Berger bullet. I used a Elk ridge bushing reamer,nice and sharp,I see what you mean about hard to clean of chips,and remove from bore,maybe a .0002 looser bushing would have been better. That's the end of the projects for know.

 

[TRECustom]

I normally chamber at 40 rpm, and pull out every .050" until I'm about .25" out, then start pulling every .020" and get on a 1" dial indicator that reads reamer advance. The dial indicator tells me where I am and when to stop and screw the receiver on and try the bolt and gage.

I try for .002" of shims between the bolt face and the go gage made up handy in the lathe. This doesn't always work out like I expect. There are enough variables that I don't ever assume that a chamber is going to have the exact headspace I want, so it is very satisfying when they do.

As for a dull reamer, send it back to the manufacturer to be sharpened, or 86 it and get a new one.

Dave Manson told me something to try if a reamer chatters,one did). Take a cloth cleaning patch,about 2" in diameter), cut a slit in the center just big enough to slip over the pilot up to the base of the shoulder on the reamer, and start reaming at a different speed. The reamer will cut the patch to ribbons but may still damp it enough to stop the chatter and clean up the chamber. It did for me. I sunk the chamber until it cleaned up,,I pulled out every .010", cleaned and put a fresh patch on each time), then just set the breech and shoulder back until it headspaced again. Saved a $300 barrel for me.

Remember, this is just my way, but I hope it helps, Tom

 

[CentrePunch]

I posted a similar question several months ago concerning my solid pilot 22-250 improved reamer from Dave Manson.
I am a retired master machinist and this was to be my first chambering.
My logic was that a solid pilot reamer would be a better tool because the floating pilot reamer would have to have clearance to the bore and clearance from the pilot to the reamer spigot allowing movement in two planes.
The clearance between the reamer spigot and the pilot bushing would have to be tighter then the clearance between the pilot and the bore otherwise the whole idea of setting up the bushing
for minimum clearance would be lost.
The clearance between the solid pilot on my reamer and the bore of my Lilja barrel worked out at .0004" which i deemed as about as good as you could get.

I opted to use a Manson floating reamer holder in order to take up any alignment discrepancies between the tail stock and the headstock of my old Colchester Master
The steady rest method was employed to do all the barrel work, so a collet chuck attachment had been previously indexed to "0" run out.
I affixed a PTG solid reamer stop to the reamer which i set +.030" on depth with slip guage blocks.
Running at 54 rpm a ran the pilot into the bore and started reaming, AAAARRGH!!!! Chatter city!
I tried different speeds and feeds but to no avail the chatter just would not go away.
Swapped the reamer into a suitable tap wrench and located of the centre hole with a dead centre.

Within a couple of revolutions the chatter smoothed out and disappeared completely.
I fed the reamer in .100" at a time with a fairly heavy feed,cleaned the chips off with the airgun and heavily applied cutting oil for the next cut.
I stopped .060" short of depth and finished the chamber revolving the tap wrench by hand whilst applying pressure to the reamer through the tail stock.
Using feeler guages i turned by hand until a .031" feeler was trapped between the reamer stop and the barrel shank face.
Bingo! all done, checked the depth with the head spaces gauges and it was spot on.
Taking up .0015" to .002" crush when the action is tightened should be perfect.
After tightening down the action i closed the stripped down bolt on a fresh Norma case and met with just about the right amount of resistance which IMO would help the cases form perfectly.
In future chamberings i will be using the tap wrench right from the onset, i must admit i was more comfortable doing it this way as i felt i had much more control of the whole process

Ian.

 

[Clark]

I have:
.308
.243
.45acp throater
7.62x54 [floating pilot]
257 Roberts Ackley
9x23mm Win
300 Win Mag
.223 .250" neck, short throat .050"
6mmBR .272" neck, short throat for 87 gr Vmax [Kiff floating pilot]
30 Mauser
17Mach2
12 ga Rem Choke reamer
.469" straight fluted reamer[45acp benchrest]
.380" straight fluted reamer[357 mag benchrest]
22LR
17M2


So only two of 15 of my reamers are floating pilot.

I don't notice the difference, except with the Parker Hale 308 bull barrel sniper trainer barrels with .2985" bore.
I could not get my solid pilot 30 Mauser reamer to fit.
I had to pound a .298" pin gauge into the throat and back out again to swage open the bore.

Also in putting a Springfield 30-06 barrel on a 91/30 we had to get a floating pilot from Manson so that we could fit in the .300" bore.

 

[3sixbits]

Ian: after reading your post in detail, a few thoughts come to mind. Straight flute reamers don't do much cutting on the body, most of the cutting is done on the front of the reamer. That being the case, you might want to consider the following.

,1) center drill and use a small boring bar.,save you a lot of chatter)

,2) Look into a lube system from Grey-Tan Rifles.,Greg's system keeps your cutting area flooded)

You indeed had the perfect fit with your solid pilot reamer. That is rarely the case, that's why bushed reamers are the only worthwhile solution.

I feel chambering off the steady rest is smart. Most of us with older lathes have a lot of wear in the bed near the chuck. How do you get around that? Only way I know is to use the steady rest.

I'm like you, the floating reamer holders must work great for some guys, I'm just not one of the guys.

One other thing I have found that really helps, is Cool Tool II, cost me almost as much to ship it to me, as it cost to buy it. But I will not cut a chamber without it, ever again! It's that good!

 

[RoyinNC]

Quote << I could not get my solid pilot 30 Mauser reamer to fit.
I had to pound a .298" pin gauge into the throat and back out again to swage open the bore. >>

Probably not a good person to take barrelling advise from......

 

[3sixbits]

I read that too. I was quiet about it. He did not say how heavy the hammer was to do that. Maybe he just did not have the right size drill bit to get him started? Or it could have been, the hammer was handier and he was pissed?

 

[Clark]

I have taken some ad hoc criticism about that pin gauge on sporterizing forum too.

That was a bull barrel I put on a Tokarev pistol.

It went to the range once and shot one 100 yard 5 shot group or 4.2" with 7.72x25mm Tokarev 86 gr S&B factory ammo and a 2x7 scope.

Here is a link to my write up of the experiment:
http://www.thehighroad.org/showthread.php?t=30127

 

[Clark]

3sixbits

Ian: after reading your post in detail, a few thoughts come to mind. Straight flute reamers don't do much cutting on the body, most of the cutting is done on the front of the reamer. That being the case, you might want to consider the following.

,1) center drill and use a small boring bar.,save you a lot of chatter)

That is allot like this:
http://www.bryantcustom.com/articles/rebarrel.htm

I then take a 3/8" drill bit and run it into the chamber end for 3/4 to 7/8". I then open the diameter of this hole with a 25/64" drill bit. After the barrel is re-indicated, I now take a cut with a small boring bar to true up the out of roundness from the drilling operation.

 

[3sixbits]

I have taken some ad hoc criticism about that pin gauge on sporterizing forum too.

That was a bull barrel I put on a Tokarev pistol.

It went to the range once and shot one 100 yard 5 shot group or 4.2" with 7.72x25mm Tokarev 86 gr S&B factory ammo and a 2x7 scope.

Here is a link to my write up of the experiment:
http://www.thehighroad.org/showthread.php?t=30127

So then you are saying that we can't have a little fun with you?,of course at your expense)

As to Mike Bryant doing something that was published in a book put out in the early 1990's by P.S. magazine,,BFI, be for Internet) what the point? If it works, what is wrong with it?

Or if you want to look back in Rifle magazine number 28 July/Aug 1973 titled Boring a Rifle Chamber by James Parfet, you'll probably say to yourself,like I do) Is there really anything new,under the sun?












I have seen these arguments and heard them about chambering for years. It really boils down to just two things.

,1) working with the equipment you have.,perhaps better said, working around the equipment you have).

,2) Getting what you want from the equipment. What is your goal?, maybe, better said, can you get there from here)?

I would advise anyone looking to get in a pissing contest, to be ware of the man with a good library and a better memory. That's just free advice. Maybe worth what it costs?

 

[Clark]

I did not invent ball sizing a hole [or in this case, a pin gauge], and I did not invent using a boring bar on a chamber.

But before I read James Parfet's old article "boring a rifle chamber", it had already occurred to me that a boring bar would keep the hole more concentric and keep my reamer sharp, if I put the boring bar in first.

I sure have screwed up a 45/70 chamber that I tried to make with JUST a boring bar.

At this time, with my limited skill level, my belief is that I should cut away as much material as possible, make concentric with a boring bar, and all finish surfaces be with the reamer.

Last month I reamed a 6mmPPC chamber out to 6mmBR. I had to just trust that the last smith got a chamber concentric to the bore. I worked out well.

Randy Ketchum, a much better smith than me, grinds a spud to within .0002" of the bore, gimbles the breech, and and dials in both end of the barrel so that the bore is concentric to the lath and co- linear where the chamber will be. He assumes that all barrels are bent.