Toolhead Clamp Kit
Toolhead Clamp Kit
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The UniqueTek Toolhead Clamp Kit™ enables the toolhead of Dillon 550, 650 & 750 presses, or the die plate of RCBS Pro 2000®/ Piggyback™ -3 & -4 presses, to be CLAMPED into the press frame. This corrects the loose fit between the toolhead and press frame, thus reducing OAL (overall length) variation and stabilizing die-to-shellplate alignment. Your press frame remains unmodified so you can still use standard toolheads/die plates with the original toolhead pins ... and your original manufacturer's warranty will not be affected.

Eliminates Loose Toolhead-to-Frame Fit
Reduces OAL Variation*
Improves Crimp Repeatability
Improves Bullet Concentricity from Seating Die
Reduces Jams at Size/Decap Die

It also reduces vibration and stops toolhead rattling when using the Dillon Rapid Trim Case Trimmer!

Works With The Following Presses
Dillon RL 550, BL 550, AT 500, XL 650, XL 750, and SL 900
RCBS® Pro 2000® and Piggyback™ -3 & -4

RCBS® Presses?
Yes! The Toolhead Clamp Kit™ works equally well on RCBS® Pro 2000® and Piggyback™ -3 & -4 presses!

What Comes in the Kit
The UniqueTek Toolhead Clamp Kit™ comes complete with all the parts needed for 2 presses and 6 toolheads in a reclosable plastic bag (toolheads not included). Each kit includes*:
Installation Tool for Threaded Inserts
9/64″ HSS Drill Bit
STI Thread Tap, Carbon Steel
12 Stainless Steel Thread Inserts
4 grade-8 Alloy Steel Clamp Screws with Moly Anti-seize Coating
4 Stainless Steel Washers
Hex-key to Tighten the Clamp Screws
Detailed Step By Step Instructions
* Quantities listed are for small sized kit.
† Intended for use on OEM cast toolheads. Not recommended for use on CNC Machined 6061-T6 aluminum toolheads (e.g. Whidden Gunworks, Dillon, etc.) as tap breakage will occur. For 6061 T6 aluminum a High Speed Steel (HSS) STI tap is recommended and are available in the drop-down menu below when ordering.

How it Works
Installation and use is quite simple. You tap threads into the two locator pin holes in the toolhead then install a stainless steel thread insert into each hole. The press frame is NOT modified. When you install the toolhead in the press frame, insert the clamp screws instead of locator pins to hold the toolhead into the frame. Leave the screws loose until you begin cycling the press and have all dies occupied by a round. Then, with the ram still in the up position, tighten the clamp screws. This procedure aligns the toohead to the shellplate, reducing jams. The clamp screws also create a preload force, clamping the toolhead against the top of the press frame, stopping the toolhead from moving during the press cycle and resulting in reduced OAL variation. Once the screws are tightened, just continue reloading as usual.

Q & A
Q: I only shoot pistol cartridges so OAL variation isn't that critical for me.
A: Let's say you are loading to meet USPSA major power factor. Chamber pressures can rise dramatically if the bullet is seated too deeply (shorter OAL). On the other hand, if your OAL is too long, you can have feed and chambering failures. Either way, it is likely to ruin your day.

Q: I only load cartridges for Cowboy Action shooting. How can this help me?
A: In addition to reduced OAL variation yielding less problems with short action carbines, the light loads commonly used for Cowboy Action shooting require a consistent crimp to achieve uniform muzzle velocities. A light crimp will not build as much chamber pressure, resulting in a velocity reduction.

Q: I'm already using a Redding Competition Bullet Seating Die. How will clamping the toolhead improve on that?
A: The Redding Competition Bullet Seating Die is a GREAT product! But it can't perform to its full potential if the toolhead is moving. With the toolhead clamped, you will achieve the full benefit of the seating die's micrometer adjustment capability.

Read reviews of the Toolhead Clamp Kit™ in the following publications!
Reloading; Product Reviews/Aug 2008. Click Here to Read
IHMSA News; Volume 19, Issue 5, June 2008, Page 8. Click Here to Read
Handloader; February-March 2006, Page 90. Click Here to Read

Customer Feedback
"Anyone who owns a Dillon 550/650 NEEDS this kit. The OAL variance for my XL650's cartridges is now 0.002″ or less - looks like factory ammo should. The ammo shoots more consistently over the chrono (better standard variation). For a competitive shooter, the more accurate the ammo, the better the results. I can't imagine using a XL 650 without the kit. Thanks again!"
— Cindy B. - Stewartstown, PA

"After switching over to the toolhead clamp I'm finding I went from .004″-.008″ of variance to .001″-.002″. I measure my variance using a ogive comparator tool to the base of the case."
— Steven S. – Boise, ID

"I would say I reduced the OAL variations and the station one jams by half (conservative estimate). Congratulations on another product that needed developing."
— James O. – Reno, NV

Options & Accessories

Large Size Kit: $49.95
The large kit contains 26 inserts, 10 screws and 10 washers ... enough for 13 toolheads and 5 presses ... plus the thread tap, insertion tool and hex key.
Refill Kit: $14.95
The Refill Kit contains 16 inserts … enough inserts for 8 more toolheads/dieplates ... plus 6 spare screws and 6 spare washers.
Tap HandleTap Handle: $5.95
This nifty "tap handle" is actually a key for winding a clock, but it is the perfect size to fit the small thread tap in our kits.

It is smaller and less cumbersome to use than a standard tap handle, making it easier to align the tap squarely with the hole and making tap breakage less likely.

We offer these as an option with both the small kit and large kit. If you already have a Toolhead Clamp Kit™, you can buy just the tap handle. Just select it from the drop-down menu.
NOTE: New Tap Handles have arrived that fit the new HSS (High Speed Steel) taps temporarily being included in all Toolhead Clamp Kits™. If you already have an old tap handle (with #5 stamped on it), it is too large to fit the HSS STI Taps.
HSS STI TapHigh Speed Steel STI Tap: $22.95
If you are installing the Toolhead Clamp Kit™ on CNC Machined 6061-T6 aluminum toolheads (e.g. Whidden Gunworks, Dillon Precision, etc.), you must use a High Speed Steel (HSS) tap. The Carbon Steel tap that is included in the Toolhead Clamp Kits™ is intended for the OEM cast pot metal toolheads and is not strong enough for 6061-T6 aluminum.
If you need a HSS STI tap, just select it from the drop-down menu when ordering.
NOTE: HSS (High Speed Steel) taps are temporarily being included in all Toolhead Clamp Kits™ … at no extra cost! But if you currently have a carbon Steel tap and need to upgrade it, they are available individually here.
If you already have an old tap handle (with #5 stamped on it), it is too large to fit the new HSS STI Taps. The Tap Handle above is of the correct size (#4 stamped on it).

Toolheads with Clamp Kit Preinstalled:
We carry CNC Machined Toolheads from Whidden Gunworks. They are available for 550, 650 and 750 presses with the Toolhead Clamp Kit parts pre-installed. Click Here for more information!

installation instructions
* Reduction in OAL variation can be highly dependent on cartridge, bullet and other factors.
Toolhead Clamp Kit is a trademark of UniqueTek, Inc.
Pro 2000 is a registered trademark of RCBS.
Piggyback is a trademark of RCBS.
Made in USA Logo

Features Benefits
Grade 8 Alloy Steel Clamp Bolts with Dry-Film Moly Anti-Seize Coating High Strength Hardware
Stainless Steel Thread Inserts Stronger than Aluminum and Prevent Wear from Repeated Use
Fits Dillon 550 and 650 Toolheads
Can be Installed on Toolheads Already Set Up with Dies No Need to Upset Die Adjustment
Press Frame is NOT Modified Dillon Warranty will NOT be Affected
Unmodified Toolheads Can Still Be Used with Original Toolhead Pins Transparent Interchangability

Customer Reviews

Average rating from 3 reviews: 5.0
Easy to install and provided tighter cartridge OAL measurements.I always wanted to try this Toolhead Clamp Kit but was concerned that I would screw up the toolhead with the drilling/tapping. My concerns were unfounded. This kit is a piece of cake to install. The directions are very thorough and easy to follow/understand. I did an install on a Dillon Toolhead and both the drilling and tapping went like "butter". The toolhead now is clamped in place and feels solid/precise & there is still side-to-side "float" in the Dillon 550 shell plate (perfect!). Don't hesitate with unfounded concerns...this is an outstanding product that is easy to install and provide tighter cartridge OAL measurements. Also, Uniquetek Customer Service/Communications is the best I've encountered in over 30 years of reloading. Written by Bob Arroyo on Tue 3 Jan 2023 4:39:19 PM GMT
I Highly Recommended ItSo I installed the UniqueTek Toolhead Clamp Kit, Standard Kit w Tap Handle and it took me 25 minutes to install. All you need is a vice, drill driver and 1/4" bit. I used the straight 30wt oil (same oil I use to lube the ram on my 750) when tapping. I got the kit with the handle for an extra $5 and it is worth it. One important thing to note is you DO NOT break the tabs of the coil, leave them in in case you need to adjust or remove. Since I have installed it, my COAL has improved and out of a hundred rounds I only had five cases hang up in station one the sizing die as opposed to 40 or 50 normally. It is a breeze to install and comes with excellent instructions. If you are interested in getting the most out of you 550/650 or 750, or if you just like you trick out your rig (I like both) I highly recommended it. They also sell CNC Toolheads by Whidden Gunworks that already have the threading installed. Written by David Asmuth on Fri 17 Sep 2021 5:34:04 PM GMT
Absolutely fantastic productI wish I would’ve known about this before! OAL variance has decreased to 0.001 to 0.002 on my 308 loads. Stabilizes the tool head for better overall performance on my 550. I’ve been adding several other items from Unique Tek and they have all made considerable differences in performance. Written by John Mattern on Sat 12 Dec 2020 3:57:29 PM GMT
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