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Custom reamers

Interesting you'd say that since I started the thread and the discussion.

So where can I find the published differences that show SAAMI tolerances vs reamer tolerances?
I’m not sure what you mean in your first sentence.
saami.org has chamber prints.
Reamer makers have reamer prints.
 
I’m not sure what you mean in your first sentence.
saami.org has chamber prints.
Reamer makers have reamer prints.
He was referring to your comment that his question about saami maximum was irrelevant. It's his thread, he can take it a different direction if he likes(although I am no expert on forum etiquette).

I am also not a reamer expert, but I always assumed that a production line reamer would be made closer to saami maximum, to allow for it to wear down a bit without going out of spec.
 
Dimensional tolerances listed on a print for Manson Reamers are Diameter +.001/-.000, length +.005/-.000, angles + or - 10 minutes. These tolerances will be the same whether custom or SAAMI spec reamer. SAAMI specs refer to the standard dimensions of the chamber but allow a bit more dimensional tolerance than the actual grinding. In other words a SAAMI dimension could be .375 diameter + or - .001 but the actual reamer will be ground to .374 +.001/-.000 in most cases.
 
SAAMI Spec Reamers are ground to specific sizes mandated by the Institute, taking into account the minor tolerances allowed. This is a world wide designation that is not supposed to vary for obvious reasons.

A “match” or minimum spec reamer can be ground to anything a particular reamer manufacturer decides. The usual idea is to take all of the sizes down to minimum so the loaded round so to speak is not “flopping around” in the chamber. The minimum spec can also feature a shorter throat so the hand loader can decide to get his loaded rounds closer to the lands if so desired but probably still be able to safely fire any popular factory ammo.

A true “Custom is ground to specifications that the customer request, and often will not safely fire any round except the rounds he makes for it. A good example is the wide variety of 6PPC Reamers. There is an official SAAMI reamer designed to shoot the original Sako PPC. However, there are many reamers in the hands of shooters that produce neck dimensions, and even web dimensions that make it impossible to chamber and SAFELY fire a “factory“ round.

All of these custom reamers are usually designed to increase the accuracy capability of the rifle.

In many cases, it is a moot point. For my Mauser project, I used a SAAMI reamer in 280 Remington. That will be perfectly fine in this Rifle whose intended use will be relegated to “showing it off” and perhaps letting a friend take it on a deer hunting trip.
 
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Interesting you'd say that since I started the thread and the discussion.

So where can I find the published differences that show SAAMI tolerances vs reamer tolerances?
Everything manufactured has tolerances; some are smaller than others. Google SAMMI approved cartridge. For a SAMMI approved cartridge, the group agreed to a diagram of the cartridge; a reamer can be built to make a chamber for that cartridge within some tolerances, so that any firearm with a chamber of those dimensions will safely fire a cartridge meeting the SAMMI specs for dimensions and pressure. An ammo manufacturer makes ammo within some range of tolerances specified by SAMMI - so that wound will fit in any rifle chambered for that cartridge. A rifle manufacturer chambers the rifle with a reamer so that it will accept all of the ammo that falls within the tolerances set by SAMMI for that round. There are errors -or tolerances. They usually allow larger rounds - + tolerance - so that the largest of the manufactured rounds will still fit, even if they get a particle of dust. Reamer tolerances can be found on the print and have little to do with SAMMI - they are the allowances for the reamer manufacturer’s ability to make the tool. Spend some time looking at a chamber/ ammo print from. SAMMI and a reamer drawing for the same round from one of the remember makers.
 
He was referring to your comment that his question about saami maximum was irrelevant. It's his thread, he can take it a different direction if he likes(although I am no expert on forum etiquette).

I am also not a reamer expert, but I always assumed that a production line reamer would be made closer to saami maximum, to allow for it to wear down a bit without going out of spec.
A production line reamer is made to the same tolerances as a “custom reamer” - same manufacturer, same individual making them. The difference between “match” reamers and “SAMMI reamers” is in the dimensions they cut. A match .22 reamer may have a shorter throat and a different leade angle - but you won’t know that without looking at the print! You CAN specify a reamer with tighter tolerances at all or some of the measurements, but cost increases logarithmically with a decrease in tolerance.
 
Dimensional tolerances listed on a print for Manson Reamers are Diameter +.001/-.000, length +.005/-.000, angles + or - 10 minutes. These tolerances will be the same whether custom or SAAMI spec reamer. SAAMI specs refer to the standard dimensions of the chamber but allow a bit more dimensional tolerance than the actual grinding. In other words a SAAMI dimension could be .375 diameter + or - .001 but the actual reamer will be ground to .374 +.001/-.000 in most cases.
Well said!
 
A2C976EE-65AE-4943-B8FD-14DEDF5383DB2023-11-07_10-15-05_993.jpegHere is a photo of a reamer print. Each box requires a value in order to manufacture the reamer. On this print tolerances are specified. other reamer manufacturers may allow you to specify that tolerance, but before you make the reamer there will be a discussion about the need for and cost of tighter tolerances than the manufacturer specifies. the ONLY difference between a SAMMI reamer and any other/custom reamer is that SAMMI specifies the numbers for each dimension - for each box. Change ONE box, and you have a custom reamer - or at least one that is no longer. SAMMI. I have dabbled in the occult world of wildcatting. Fun, but costly. When you are looking for a custom reamer, you start by telling the manufacturer what you are trying to accomplish. Often, someone has already tried it, or has gotten close. They will send you prints and numbers to study. When you have the numbers ready, there will be back and forth, as in this fax copy, to make sure you are getting what you want. I have one wildcat that uses a standard reamer, then a neck reamer, and finally a throating reamer, as that approach was much cheaper than building a new reamer.

C4060AAD-0276-479C-BC24-2B3CA6EAD3522023-11-07_10-17-48_732.jpeghere is an example of just a few of the rimfire reamers available from this manufacturer. Some of these are SAMMI reamers. Notice that there need be only a few thousandths difference in the specs and it is no longer a SAMMI reamer. Hope this helps!
 
And those are reamer specs. The reamer will cut a chamber close to those dimensions depending on the skill of the user, then quality of the steel in the chamber, your ability to keep chips out of the chamber and reamer flutes, and at least a few other factors I have not mastered/experienced yet! ;-(. We hope the ammo is smaller than the chamber, but not too small.
 
Forpest, thank you for taking the time to make make your posts.
Sometimes it takes a different explanation to convey ideas and I appreciate that you made that effort. I now understand what you were trying to explain.
 

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