Sinclair International Reloading Tools

22 May 2000
By peteR

    In some of the past few articles that I have posted mention has been made a number of Sinclair International's precision reloading tools.

    While certainly not all real-world/real time tactical shooting or sniping (either L-E or Military) is done with custom manufactured ammunition for possible legal ramifications (More likely the fear of vicarious liability), many of us do utilize handloads for practice and competitions.

    Factory ammunition is made to very good tolerances for the most part and their Q-C is far better than in the past, due greatly to technological innovations and improvements.

    However, once in a while there can be a glitch and a batch may slip through the cracks that are a little less than perfect.  Some representative examples are primers loaded backwards, or in a worst case scenario, no flash holes, or powder charge, or...

    Mechanical thingees like commercial reloading machines (Real Big Ones!) go out of adjustment and this may not be caught before the ammo departs the facility.  Production standards may also be somewhat looser than accuracy aficionados demand for extracting that last hundredth of an inch from a group aggregate.

    Contract Purchased components like Match type projectiles, may not be within the parameters serious shooters find acceptable regarding weight variances, runout, core bonding or half a dozen other things beyond the ammo makers' control.

    If you are serious about accurate rifle shooting then you probably already visually inspect your rounds, and probably weight-select them as well.  I have done so for over a decade, even with handgun ammo used for defensive carry.

    Simple prep work, like a visual inspection and weighing, probably will not give you sub-1/4 MOA groups through a stock or semi-stock tactical rifle, but can level the playing field when testing factory ammunition and/or handloads, and help to minimize variables resulting in more consistent shot strings.

    I am going to cover briefly some intermediate and advanced tools for reloading precision rifle ammunition and my limited experiences with them.  I'm not professing to be a bench rest guru, "Master Sniper" or anything else, just passing on some preliminary information and comments for those interested in the subject matter.

    There are a number of published text books on both simple and advanced reloading techniques that should be mandatory for a shooting library starting with the Hornady, Hodgdon's, Sierra, and Speer Reloading manuals, Precision Shooting's Reloading Guide, The Ultimate in Rifle Accuracy by Glenn Newick, and Sinclair International's 10th edition Shooting and Reloading Handbook.

Concentricity Gage and Neck Wall Thickness gage
Case Trimmers
Chamfering Tools
Phase II Primer Pocket Uniformer
Flash Hole Deburring Tool
Sinclair Phase I Neck Turning Tool & Kit
Sinclair Bullet Comparator
.308 and .300 Win. Mag Tested

Concentricity Gage and Neck Wall Thickness gage

Measuring Neck Wall Thickness Variance
Measuring Neck Wall Thickness Variance

    One of the most versatile tools Sinclair produces is the Concentricity and Neck Gage for measuring both bullet and case neck runout.  This tool allows the average shooter to inspect their factory, or hand loaded ammunition for concentricity at the neck and bullet quickly and accurately.

    Other concentricity tools are out there, but Sinclair has established a reputation for quality for non-custom equipment that keeps prices reasonable.  Use of the concentricity gage is simple, complete assembly following the clear instructions and set the dial indicator tip to rest on the case neck (I like to use a point about mid-neck) and gently rotate the cartridge in the Vee groove.  For loaded ammunition the indicator dial will fluctuate with the amount of runout or misalignment from the cartridge body to the case neck.

    The same step is then done to check bullet runout by moving the indicator bracket outwards about another 1/4" or so to mid point on the exposed projectile ogive.

    My only two personal gripes with this particular tool, was that the machining in the "Vee" groove seemed a little rough, and the cases seemed to slightly vibrate or chatter.  A piece of UHMW (Ultra High Molecular Weight) self-adhesive plastic strip was cut and placed on both of the sides of the groove. This eliminated the chatter problem and reading the cartridge became both much smoother and faster to accomplish.

    Secondly the indicator tip kept coming loose and has to be retightened.  I am hesitant to put thread sealant on measuring tools and could have replaced it with a Starrett Roller Contact Point (part #25) if the dial indicator was to be permanently mounted n the fixture.

    Note: A revised version with roller bearings was released in early year 2000 to make case rolling FAR easier and smoother.

    The Case Neck Wall Thickness gage (provided either as a kit component or two separate gages) allows the sharpshooter to check new or fired brass for variations in neck wall thickness.  These can affect both projectile seating concentricity and possibly alignment between the round and the chamber/bore lead. The choice can then be made to Cull - Neck Turn - or Load as is.

Here is a pair of examples which will be covered again later in the article:

  1. My 200 round batch (two boxes) of Federal Gold Medal.308 (#GM308UPl;) brass showed a neck wall thickness variation of from .0005" to .0045".  The average measurement being .0025" and over 70% of the cases fell into that range.
  2. Two 100 round boxes of Federal Gold Medal .300 Winchester Magnum (#GM300UP) brass showed a showed a neck wall thickness variation of from .0015" to .0030".  The average measurement being .002" and over 85% of the cases fell into that range.  The two boxes of .300 showed much better uniformity than the .308 and the .300WM case mouths showed much less shipping deformity.
    Without getting into toning the bench rest Mantras, more arcane "Ju-Ju" and/or "Voodoo" too far, let me say any neck misalignment is not a good thing!  Sinclair recommends preliminary culling of cases with a variation of more than .003" variation until they are neck-turned for uniformity.

    First above every thing else for us tactical rifle shooters is 100% reliability followed real closely by accuracy for each and every shot. I know: "peteR- Whoa hold on a Minute Of Angle".  Well that's the way is it, bottom line!

    A finely crafted, polished gem that gets crud on it during an observed stalk and is loaded with muddy hands and locks the rifle up has just defeated its purpose.  Too many "what- ifs" for this simple county boy to keep up with.

Case Trimmers

    An EJS Kwick-Case has been on back order as of the time of this article commencing, a very hard item to keep in stock I guess.  This goodie trims the neck of the case square with the body and uses the cartridge datum line (roughly the case neck shoulder junction) to set for a consistent length to SAAMI standards.  The Kwick-Case trimmer is faster to use than the conventional lathe type case trimmer, and it does a far cleaner job than a trim die.  It can be mounted up in a lathe and used very rapidly to trim brass to length.

    I have been using a Forster Case Trimmer with collet clamps for twenty years and it has served very well with just a slight bit of rust patina on the cutting shaft being the only obvious showing of age.  Sinclair sells a power trimmer adapter that lets one use a cordless screwdriver or drill to crank out cases quickly.

Chamfering Tools

    Chamfering the case mouth accomplishes two things: First it facilitates even entry of the projectile base when the seating operation takes place.  This has been proven many times to be the most critical part of the projectile.  It is the last segment of the projectile to leave the muzzle/crown and most exterior ballistic factors are believed to be controlled by the rear stability of the bullet at all velocity ranges.

    The key is to only break the sharp edges just lightly kissing the mouth of the case and not remove too much brass.  I use a Lee tool that was a donation from a friend.  It does both the inside and outside with but a single cutting flute.  It can be chucked in a lathe or power screwdriver and cases done rapidly and accurately.  Most production deburring tools like Sinclair's are multiple toothed and do an equal and perhaps better job.

    Recently a newer variation with a more acute 14-degree angle designed to seat the newer match type or VLD projectiles has been released.  Holland Gunsmithing and Lyman offer these VLD-type chamfering tools for inside mouth chamfering only.  Any time the cases are trimmed and the mouths squared, lightly chamfer them.

Phase II Primer Pocket Uniformer

Sinclair Primer Pocker Uniformer
Sinclair Primer Pocker Uniformer

    The Phase II Primer Pocket Uniformer consists of a small plastic handle with a removable cutting blade assembly.  This tool is pretty straightforward to use.  You insert the four bladed reamer into the primer pocket and gently press inwards and rotate to remove the slight hump that is made during the brass blanking /primer pocket forming step.

    The tool came pre-set to cut the pockets to a depth of  .130" and can be adjusted to a lighter or deeper cut if you wish to dabble in "Voodoo".  Be warned misfires can result if the primer pockets are cut too deep so mine was left at the factory supplied setting, conversely cutting the pockets too shallow could result in serious safety issues.  But that is moot as a result of SAAMI manufacturing specs.  All primers will now seat squarely to the face of the cartridge and a consistent uniform depth in the casing with a minimum of fuss and muss.

    It is recommended that reloading ram type primer presses are bypassed and either a high-grade hand tool or bench-type priming tool is used.  I use a neolythlic RCBS bench primer and have developed a good sense of "feel" for seating primers over the years.

    I removed the tool handle from the Phase II Primer Pocket Uniformer after manually doing my very first 100 cases and the process taking over 1.5 hours.  I removed the handle and chucked the tool head/reamer in my mini-lathe set at 600 rpm.  If you use a power tool (lathe, drill press, power screwdriver) remember to make two light cuts and allow the brass chips to be ejected from the tool.  The next 100 cases incidentally were finished in less than 30 minutes including both set up time and cleaning up the lathe after the fact.

Uniformed Primer Pocket
Uniformed Primer Pocket

Flash Hole Deburring Tool

    The cup extrusion method commonly used to make commercial brass also leaves a burr inside the case when the primer vent hole is punched.  This needs to be removed to allow for more uniform ignition of the powder column.  The deburring tool is a small countersink affixed to a piece of hardened rod with a collar controlling the depth of chamfer/cut.

    The tool I own/prefer is the Sinclair Deluxe deburring tool.  Its travel stem is long enough to use with all conventional rifle cartridges over .217" caliber and the tapered lock collar eliminates the need to buy additional fittings or widgets.

    Slide it into the case mouth, align the small end of the countersink in the flash hole and rotate and press inwards.  The tool removes the punch burr and lightly countersinks the case web in one simple motion.  Incidentally, an integral stop collar around the cutting blades prevent the removal of too much of the case web.  The flash hole is then finished for life, never, ever, needing to have the process repeated!

    Don't use this tool under power as the brass chips will load up in the stop collar which controls depth of cut.

Sinclair Phase I Neck Turning Tool & Kit

    I use this tool simply to clean up the necks as my current tactical rifles have factory chambers and tolerances are a just a bit looser than a custom barreled rifle.  This usually involves a paring of about .002" from the exterior of the factory case necks.

    The process is much like making a light truing cut on a piece of stock with a larger lathe.  The key is to remove just enough brass to true the neck around the mandrel.

    The neck turning kit consists of a series of interrelated components that allow the user to hand turn the necks of the cases to a consistent thickness/diameter to provide an even release of the projectile.  At the same time this step hopefully keeps the bullet concentric with the chamber lead enhancing accuracy.

    The version I obtained did not have the new Sinclair jig plate to mount the cutting assembly which utilizes a dial indicator to set and monitor the depth of the cut into the case neck.  This could be a very beneficial addition to the large case volume precision reloader.  I do plan to obtain one in the very near future and simplify this task.

    The cases are first cleaned up and prepped in the usual manner and then run through a special sizing die/mandrel assembly (provided as a single ended unit to prevent confusion with the turning mandrel) to iron out dents and dings in the virgin cases neck/mouth.  These are the atypical shipping and handling dings found upon opening the bulk brass boxes that are generally a pain in the patootie.  The sizing mandrel also slightly "bumps" up the internal diameter of the cartridge neck.

    My Redding Competition Die sets do not have expander balls and this takes care of this problem before loading.  The mandrels can also be used to progressively size up the diameter of a cartridge case neck if you are making say, .260 Remington from .22-250 brass, or something similar in effect.

    Once this step is done optimal fit of the case neck on the turning mandrels (double ended) is completed.  A bit of Imperial Sizing lube, or STP, on the turning mandrels ensures the cases turn smoothly and do not bind or gall the cases.  This ensures a smooth even cut by the carbide tipped blade.

    HINT:   Always start with a very light preliminary cut as you can always go a little deeper if necessary to true the necks.  After you have finished make certain you clean the mandrel lube from the inside of the case. I forgot once and had this neat little blockage of powder kernels develop making a real mess of the loading block with the remaining 42.0 grains of powder or so....

    This is a somewhat slow tedious process and will require patience and probably a couple sacrificial cases to perfect your technique.  There is the option of using a power screwdriver and Sinclair case driver/shell holder to speed up the process.  I guess that I feel the time, patience, and hand labor required is therapeutic giving me a sense of personal handcrafted satisfaction, and have not yet gone that power tool route.

    Make sure you clean the chips/particles of brass from the assembly regularly with a small paintbrush.  I like to use Venco Industries Quick Scrub III spray cleaner to blast out the lube and chip buildup and then apply a light coat of their Rust Prevent oil before putting the tools away till the next batch needs to be worked.

Sinclair Bullet Comparator

    Once you have found the load that shoots great through your rifle you may wish to swap bullets and try another brand or weight.  Within reason and with moderate loads many projectiles can be interchanged.  My favorite .308 Winchester load consisting of 44.0 gr Hodgdon's Varget is a good example.  I can use bullets from 155 gr. PALMA up to 178 gr. Hornady National Match and get very good replicable results.

    The catch is overall length variances caused by manufacturing tolerances and proprietary changes in the secant ogive of the selected bullets.  Loading and measuring overall length can often work but a problem I have found is the "hollow tip" often is slightly irregular and gives inaccurate readings.

    Precision dies like the Redding Competition Seater work off the secant ogive and not the meplat.  A bullet Comparator and a dial caliper make measurements quick and accurate.  I obtained a Sinclair Comparator as it's a multi-functional tool and incorporates six major calibers from .224 to .30 caliber in one stainless steel unit.  No bits and pieces to worry about losing in the workplace clutter.

.308 and .300 Win. Mag Tested

Testing .308 Loads
Testing .308 Loads

    As a simple test, I left 25 cases "As Is" from the same lot of 200 cartridges of unprimed virgin Federal Gold Medal Match brass in each of the selected calibers, and placed them in a MTM ammo box with a slip of paper designating the modifications.  I chose the Federal Gold Medal Match brass based on my good experiences in the past, but the same could be done with any other brand.  This is designated as "OEM".

    I then took some of the total remainder of the cases and prepped the primer pockets, deburrred the flash holes, chamfered the mouths inside and out, then followed this by weighing each casing.

    25 more rounds were selected and this time weight and neck thickness were somewhat "controlled" by running them through the concentricity gauge and keeping the neck thickness to within .0015" - .0010" indicated runout.  All of this prepped Federal .308 brass (denoted on table as *) was kept to a weight of between 177.3 gr. and 177.8 gr. - I could have gone to a tighter variance control on weights but did not out of complacency.

    A random selection of 25 more weighed and uniformed .308 cases was made, and the necks turned in two very light cuts.  This gave an average wall thickness of .015" for this final batch.

    The .308 Winchester loads were assembled in a set of Redding Competition Neck Size Dies. (Denoted as **) This unfired brass was neck indexed to .001" and the same loads assembled in a set of Redding Competition Neck Size Dies with a .337" Titanium Carbide size bushing for an overall length of 2.835".

    The .300 Winchester Magnum loads were also assembled in a set of Redding Competition Neck Size Dies with a .334" Titanium Carbide size bushing for an overall length of 3.650".  I have the .332" and .333" TiN coated size bushings for fine-tuning at a later date.

    The first batch of 25 cases was left as removed from the box and then loaded.

    The .300 Win. Mag brass * was kept between 247.9 gr. and 248.6 gr. and measuring the cartridge necks to obtain those between .0015 - .0010" runout on the Sinclair neck gage.  After reaming the flash holes fore and aft, and uniforming the primer pockets this brass averaged 248.3 grains.

    The .300 Win. Mag brass ** was kept between 250.0 gr. and 251.0 gr.  Then the pockets and flash holes were reamed, and the cartridge necks concentricity measured to obtain those between .0025 - .0015" runout on the Sinclair neck gage.  This group #3 was then neck turned to get an indicated neck runout of .001" or less on the Sinclair neck gage.

    The propellant selection for both calibers was from Hodgdon's Powder with Varget and H-1000 being selected for their positive results in preliminary velocity tests in each caliber.

    The preliminary charge selection for my particular rifles was 44.0 gr. of Varget in the .308, and 80.5 grains of Hodgdon's H-1000 in the .300 Win Mag.  I will try RL-22 powder next based on positive comments from a number of .300 enthusiasts.  Another propellant on the near test horizon is Western Powder's Ramshot brand "Big Boy" for the .300 Win Mag., many favorable things are being said about this powder upstart.

    The same powder charge weight was used for all 75 rounds in each of the calibers and were individually thrown from a geriatric RCBS Uniflo powder measure (w/o Powder baffle).

    The factory .308 brass was filled with throws after the scale was calibrated to 44.0 grain average over ten charges and left alone when the powder was being thrown into the rounds.

    I like to throw a series of 25 - 50 charges at a time in a loading block arrangement as the consistency and rhythm gives good results with my equipment.  Each round is then carefully weighed out on a Dillon Terminator scale (believed accurate to + or - 0.1 gr.).  Light charges were carefully brought up to exact with a powder trickler, and any heavier charges were thrown back and re-done to give exact charge weights.

    Primers were all Federal Gold Medal Match obtained in bricks of 1000.  I used GM210/.308 and GM215M/.300 WM.  The ignition results and velocity consistency with Hodgdon's powders are exceptional with these primers at all temperature ranges and conditions that I normally shoot in.

    The Projectiles chosen were Sierra Bullets' 175 gr. MatchKing BTHP's for the .308 Winchester, and 190 gr. MatchKing BTHP's for the .300 Winchester Magnum.

    My goal is to come up with equivalent loads to meet, or possibly exceed, two of the most highly rated US Military sniping rounds; The .308 M-118LR and the .300 Winchester Magnum Navy DODIC A191 NSN 1305-01-018-1547 cartridges for performance. The desired velocity windows are 2650-2700fps/.308 and around 2900-3000fps in the .300 Winchester Magnum.

    These were fired over a Oehler 33P chronograph set at 15' from the muzzle in a series of five consecutive 5 shot groups at 100 yards.  The results are listed below and with the .308 show a decrease in average group size from an OEM firelapped barrel of about 30%.  This is not a bad improvement gain for the minimal physical effort involved in gaining it.

.308 Winchester handload accuracy five 5 shot groups @ 100 yards

Group 1
Group 2
Group 3
Group 4
Group 5
Group Avg.
.308 Win. OEM
.308 Win.*
.308 Win.**

.300 Win. Mag.  handload accuracy five 5 shot groups @ 100 yards

Group 1
Group 2
Group 3
Group 4
Group 5
Group Avg.
.300 Win. Mag. OEM
.300 Win. Mag.*
.300 Win. Mag.**

.308 Winchester load velocities @ 15' via Oehler 35P chronograph

 .308 Winchester
2699 fps
2643 fps
50 fps
2651 fps
29 fps
 .308 Winchester *
2720 fps
2666 fps
54 fps
2585 fps
21 fps
 .308 Winchester **
2710 fps
2686 fps
24 fps
2693 fps
9 fps

.300 Winchester Magnum load velocities @ 15' via Oehler 35P chronograph

Win. Mag.
3027 fps
2963 fps
64 fps
2960 fps
23 fps
Win. Mag. *
3039 fps
2988 fps
51 fps
3002 fps
18 fps
Win. Mag. **
14 fps
2977 fps
07 fps

.308 Winchester Test Components

 Lot Number
Federal GM308UP
Sierra 175gr. BTHP
July 22, 1998
Hodgdon's Varget
Federal GM210

.300 Winchester Magnum Test Components

 Lot Number
Federal GM300UP 
Sierra 190gr. BTHP
Sept 1997
Hodgdon's H-1000
Federal GM215M

    These are a little above the basic reloading techniques used by the average shooter, but with a few additional simple steps using these hand tools one can go a long way to enhancing the performance of your handloads.  I feel that there is great merit to increasing the potential of a long-range load by minimizing these variables.  Just remember the caveats on 100% reliability for ammunition to be used in the field.

Sinclair Case Preparation Tools
Sinclair Case Preparation Tools

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