Chamber Reamers

Chamber reamer prices
Prices for reamers made to CIP specifications or SAAMI specification are listed on this page. Prices are based on the size of the base of the corresponding cartridge. For example, a 308 Winchester has a base diameter of 12.03mm so this is a 'Regular' reamer. 'Magnum' reamers (for example, a 300 Win Mag.) are defined as reamers with base diameters greater than 12.5mm and Large reamers (for example, a 50 Browning) as having base diameters larger than 15.5mm.

For non-standard reamers made to your specifications, or changes to the dimensions on standard reamers, there will be a surcharge of £25.

Delivery times
We keep a wide selection of standard reamers for the more popular cartridges in stock on the shelf for most of the common cartridges and we can usually post these out to you immediately.

We also keep a number of machined and hardened reamer blanks on the shelf, so if you want a non-standard dimension such as a tight neck or longer throat on a standard reamer, we can normally turn that around within a week.

For reamers which we do not have in stock and have to be made from scratch, we can normally make these within two weeks. Due to the innovative CNC software which we have created, we can very quickly turn a chamber or reamer drawing into the necessary G code for our CNC lathes and milling machines to make the machined reamer blank, and also to create the dxf file so that the hardened reamer can be finish ground .

Steel Reamers for the more common cartridges are normally finish ground from stock blanks which are machined from M2 high speed steel and hardened to about 64 HRc. Reamers for which we do not have a blank in stock are made in O1 tool steel which we harden and temper in house to a hardness of about 61 HRc.

Carbide reamers, usually used in production barrel chambering, are made to order.

The shank size at the back of the reamer is generally 11.113mm (7/16" or 0.4375") which is the standard amongst US manufacturers. Large reamers such as 50 BMG or 12 bore will have a 19.05 (3/4" or 0.75") shank size. All shanks will usually have a flat on the side.

These days, gunsmiths will usually chamber a barrel in a lathe using a reamer holder in the tailstock, so we do not generally put a square end on the back of the shank. If you want a square back end on the shank, please specify this in the order and we will put one on at no extra charge.

Carbide reamers are generally used in production on a CNC lathe, held in a metric collet tool holder. Please specify the shank diameter you want if different from our standard 11.113mm (7/16" or 0.4375")

Pilot bushings and pilot spigots
Our standard and magnum chamber reamers are made to use 12.7mm (0.5") long floating pilot bushes as standard. The pilot spigot sizes will be the same as that generally used by chamber reamer manufacturers in the USA. Our pilots are therefore interchangeable with those used on most chamber reamers made in the USA. We do not supply reamers with pilots as standard. (Most gunsmiths who have used reamers from US manufacturers will probably have a draw full of pilots bushings which will fit our reamer anyway). If you need a pilot bushing with the reamer, a pilot can be purchased separately.

Our large chamber reamers will generally have a 7.5mm x 12.7mm pilot spigot, which is not a standard used by any other manufacturer, and so pilot bushings will be supplied with the reamer.

Standards and tolerances
Our chamber reamers are made to CIP specifications unless otherwise specified. You may also request a reamer to SAAMI specification or use our custom reamer form to specify your own chamber dimensions. Both CIP and SAAMI specify minimum chamber specifications, which means the chamber should not be smaller than this and we will generally make our reamers with diameters about 0.05mm (0.0002")to 0.01mm (0.0004") up on those specified so that they wear down to minimum size rather than wear under minimum size. Finisher reamers will include the lead and throat. Roughing reamers will not include the throat and will be made with all diameters about 0.15mm (0.006") undersize.

Getting the best out of your BBT chamber reamer
We have prepared some notes on the use of our chamber reamers to help you achieve good results and long lifetimes from our chamber reamers.