45-120 Case Flash Hole Reaming

[bigbore52]

Have a question for those who load the 45-120 and in particular ream the flash holes on the big 3 1/4" case - can you please advise what sort of tool you use for the job?

I have found that most commercially available Flash Hole Reamers from the usual brands are not long enough for the case so had to make up my own tool - it works but it's not ideal and as I have a new batch of several hundred cases to ready, was wondering if there's anything available out there better suited than my prefab job?

Have dropped a few questions to various manufacturers on shaft lengths and suitability of their products etc but still waiting on replies so any suggestions would be appreciated tks...

[montana_charlie]

When you say 'ream', are you talking about changing the diameter of the flash hole ... or just cleaning up any burrs that exist inside of the case?

For burrs, I use a gentle spin with a drill bit ... Just enough to get a 'smooth feel'
Surely you can find one of those that's long enough.

As for drilling out flash holes ... I don't know anybody who still recommends that.

CM

[country gent]

I have made thedeburring tools with a small center drill (1/8" body not sure of the number right now) chick up a piece of 3/16" round stock and face one end then drill a hole in center to allow center drill to be pressed or glued in place. Cut longenogh for a handle and your good to go. As to reaming same could be done with the size drill bit you want to ream to set into rod so its nice and short long enough to cut thru with a few sharpenings extra length.

[bigted]

I just use my Lyman primer hole deburring tool ... it unscrews from the handle and I install it in my chucked tool that is hex with the same internal threads of the shaft ... I then turn it with my SLOW screw gun that is internally batt. charged ... read a SMALL and SLOW screw gun.

this works well for all my needs and when you take the tapered stop off the shaft it adds enough length to ream successfully.

[bigbore52]

Thanks gents - appreciate the suggestions.....I do both, remove the burrs and ream the flash holes on all my cases as a reloading process for virgin brass....was toying with the idea of cutting an existing tool such as the Lyman Flash Hole deburr tool and extending it but not sure if there's a commercial made one of suitable length already as it would be much easier and quicker than fabricating one.

Have found that some bits, particularly the newer style multi facet cut ones remove more brass inside than needed given their edge angle and are a bit finicky to setup without some form of pilot through the flash hole as a guide - hence my preference for the commercial style

I do like your suggestion as a work around cg - nice and straight forward...have to check what centre drills I have in the tool box now :)

[bigbore52]

Thanks bigted - posted reply as your post appeared - I have sent off a few queries to various manufacturers hoping they would provide a measurement so I could see which ones fitted but so far no replies - Brownells suggested the Lyman may fit but weren't sure either. Your answer explains the problem...appreciated

[THerbert]

Center drills are available in 6" length, just check with your nearest tooling supplier. Then just chuck it in your cordless drill and go to it!

[fouronesix]

Enlarging flash holes is kind of "out of fashion" so to speak if that is what you are wanting to do. Also why the need for a really long numbered drill bit since you can drill (or ream?) from the base end of the case?? If it's a simple matter of cleaning up the flash holes for uniformity with no enlarging, just take put a numbered drill bit of our choice into a pin vice and do it by hand.

If you are just looking to ream the flash hole to standard spec and de-bur the interior, the Lyman Uniforming Tool tool is plenty long at 3.7" and is by far the best method.

[bigted]

Enlarging flash holes is kind of "out of fashion" so to speak if that is what you are wanting to do. Also why the need for a really long numbered drill bit since you can drill (or ream?) from the base end of the case?? If it's a simple matter of cleaning up the flash holes for uniformity with no enlarging, just take put a numbered drill bit of our choice into a pin vice and do it by hand.

If you are just looking to ream the flash hole to standard spec and de-bur the interior, the Lyman Uniforming Tool tool is plenty long at 3.7" and is by far the best method.

yes and thanks for the pic's of it. is exactly what I were speaking to above ... this werks very well and by the way the portion that screws into the handle is the same as my brass cleaning brush's and cleaning jags.

[bigbore52]

Thankyou gents.....I contacted Lyman as mentioned and they suggested their flash hole uniformer "may be long enough" but weren't certain and strangely would not advise how long it was when I asked - I ordered one all the same. Thanks fouronesix for the measurements and pictures, that's nailed it.

I have several older tools (not Lyman) which are labelled similarly but each one has a shroud over the end stopping the chamfering from working. Why they are made so confuses me unless they are made specifically for those cases which have a cupped base to the flash hole....these days, nearly all the cases made to my knowledge have a flat base on the inside which the holes are punched through but I have seen ones which they'd fit, just not in my collection. A quick read through Dunlap and others shows several rarer examples.

Equally I have some long centre drills with the 5/64" drill being almost the identical size that my 45/120 Norma brass is so have that covered.

As a normal process on all virgin brass I uniform the flash hole only - never enlarge it, and remove any burrs from the inside prior to annealing the cases. I don't touch them again aside from cleaning the primer pocket and hole each reload with the occasional anneal. You could say its a force of habit but each to their own so my existing tools didn't reach down the 3 1/4 case to de-burr hence my initial query.

It's just something I've done for nigh on 50 years of reloading ....but happen to be a relative newbie to the 45-120 case and enjoying making much smoke with it......thankyou for your replies and suggestions.....all the best and straight shooting

[fouronesix]

There'll be a tapered, centering bushing with set screw on the shaft. Remove that bushing for the full 3.7" length if needed. I use mine with or without that bushing. You can tell when the reamer has removed any burs surrounding the flash hole. I have noticed no inconsistency when using it this way- a light touch by feel.

If desired for concentricity, you can add a 45 cal bushing on the end- sometimes I've even used a few wraps of masking tape.

I've been using the tool for a long time and while it is one of those tedious brass prep operations… it only has to be done once to new brass. And, whether or not it's needed depends on the type or brand or brass. Some, like Norma or Lapua, may not need it as they are drilled or don't have interior burs. While other brands that have punched flash holes can have huge burs, even overhanging flaps of material around the flash hole. I do it once to all new brass then know for sure there are no burs and all the flash holes are consistent.

[Sharpsman]

About as useful an operation as having tits on a boar hog!!

[fouronesix]

About as useful an operation as having tits on a boar hog!!

You sound pretty sure about that and have significant experience with a wide variety of brass.

For some types of brass it is not needed. It's only done once, won't hurt anything and at the least will make for one less variable where all the flash holes are consistent. On the other hand- I've had new brass (major US manufacturer) with the common punched primer flash hole where the interior punched burs were significant. Some even had the punched flap burs covering the flash hole.

[Red River Rick]

Reaming? Deburring would be more the process.

And, unless you have a lot of "burrs" around your flash hole (poorly manufactured brass), I have to agree with Sharpsman, it's a unnecessary operation unless really needed.

RRR

[fouronesix]

Reaming? Deburring would be more the process.

RRR

Yes, I think that the OP's wording hinted at that (reaming) and it was hashed out and clarified earlier in the thread.

Benchrest and serious target shoots have been doing it for years. And yes, some brass is made using techniques that don't require it. But to dismiss it out of hand shows either lack of knowledge about various brass and various lots of brass or in the camp that doesn't care about getting the most out of consistent reloading by eliminating easy-to-eliminate variables. Some in that camp are perfectly happy with ammo that goes bang. It's easy to do, takes little time and only has to be done once.

[bigbore52]

Gee, didn't think there was much fuss on what verb was used to describe the process and how topical my post was - whether the hole was reamed, uniformed or deburred...Having a background in machining, was always taught reaming is a process used to uniform a hole whilst de-burring is a completely separate process. That's why there are different tools made for each job, reamers and de-burrers...

I took your advice THerbert and used one of those extra long centre drills which as you know, incorporate a chamfering aspect - happened that the one I used to "ream" the flash hole had a drill bit of 5/64 on a 3/8 shaft and was 6" long.

Now whether it's actually needed or not is up personal preference but with these virgin Norma cases, found a considerable amount of brass flakes removed from both the reaming function as well as the chamfering which indicated lots of burrs present on the inside lip of the flash hole. Not only that but many of the flash holes were not uniform size and equally not centered in the cup....some flash holes required "reaming" others did not which meant they were over 5/64.....I'd imagine of the 100 case I did, about 70% had burrs present and 10% had flash holes greater than 5/64 - very few were sized at 5/64 and free of burrs....that's not what I experienced with Norma brass purchased few years back

Admittedly I also haven't purchased Lapua for several years but the last lot was much more uniform that this batch of Norma - be an interesting exercise to see how they now fare given price increases for labour and materials etc?

I expected similar with Norma but that wasn't to be - it's no big deal with the 45/120 case bearing in mind there is limited stock available - to my knowledge only Norma, Bertram and formerly Bell (have no idea who they sold to since) made or still makes them....so it's take what you can get...as for making the brass myself, much too time consuming

I don't use any mechanical process in uniforming them for such a small volume run, rather all done by hand and that way you can feel if the tool is actually cutting into the brass or just smoothing the lips and arris' which is the correct method. I doubt a mechanical process would pick the difference and you are correct fouronesix, certainly need to set a lock stud on the shaft to limit depth of travel...in lots of other caliber cases I do use the mechanical process and you can see in some, burrs do block the flash hole...

That being said, I don't have any technical data on this case as to whether removing the burrs and uniforming the hole (by reaming it) adds to accuracy or not and that's why I am not overly fussed with the cases that had over sized flash holes or not centrally located - With BP cases I doubt it would, but it's a process I follow with all my virgin brass, including this case. Now if others believe it equates to a useless procedure, then they are entitled to their opinion but I would suggest they speak to those shooters who consistently win distance matches - it is a proven way to attain consistency and hence accuracy......that's a fact

Thanks for you help and suggestions - the tool worked a treat.....straight shooting :)

[fouronesix]

Good you got a tool/bit that does the job. Unusual that Norma had some burs and some off center holes. I've used Norma and Lapua over the years for certain cases and they are usually two of the best for uniformity, including the way the primer cups and flash holes were formed (very consistent and without burs). Could be that Norma is using different (maybe older or out-of-adjustment) equipment for forming some of their brass.

I know for a fact that some of the Winchester seasonal or 'special run' brass has had some wide variations- such as incomplete flash hole punching, etc. I would cut the head off a new one and post a picture but the caliber is sometimes hard to get and expensive, so anyone doubting just has to take my word. The Lyman de-burring tool does the correct job for saving those cases and they are now fully functional.

And I believe you are correct that the de-burring/uniforming can be done by feel since such small amounts of material is removed in the process. When I was loading a lot more for bench rest comp., I tried both the tool stop feature as found on the RCBS, Lyman and other such tools. Seemed I was just as consistent using the 'feel' method as by using the stops. And for certain no difference in accuracy was noted.

[bigbore52]

Have to agree with you there - have also found the quality of brass by different manufacturers has fallen in recent years - my experience used to be that Lapua was by far the best, followed by Norma then generally Federal but Lapua was way out of price comparison, almost double other brands - still is in some regards and unfortunately they don't offer as big a range as other brands do

For my hunting loads where my hide depends on it working properly first go, then I use a case I know to be well made and not likely to split or separate at a critical time, I always use my own reloads, never factory loads - quality to me does matter in those instances..so I can't blame anyone else :)

As an example, I shoot the SMLE and have found that particular case probably less tolerant of the different brass offered - I have sacrificed many new cases measuring the construction of walls, necks, bases etc and keep notes of each brand as a reference - found the cheaper brands generally have thinner or less metal in them even though they may weigh the same in total so that weighing the cases doesn't tell you the problem....generally they suffer poor construction in the primer pocket size, bored too deep or too small and most holes are off centre - reloaders would have experienced similar but some brands have more issues than others so it gets back to how they are manufactured and the quality control used - I won't mention a particular brand, but noticed over the years, the case walls and necks of the new 303 brass I was using getting thinner and even annealing didn't extend their lives to any degree. Wasn't alone there, some fellow shooters were experiencing case separations and neck splits on first firing with the same brand of brass.....changed brands and problem gone but that shouldn't arise at all!

Now this all gets back to the type of reloading you do say neck size vs FLS and annealing etc but when a case shows signs of fracture or stress after the first firing, and you know there is nothing wrong with the gun as other branded cases work then you begin to wonder.....

That's one reason I use the same processes in my reloading irrespective of the case ...

The tool I used is called a 6" long Combined Drill and Countersink - this particular one has a 5/64 drill bit on a 1/4" shaft I believe and can be purchased at most machinery shops for less than $10 - will certainly do the 45/120 case and just about every other case known with the probable exception of <22 cal necks...but for those you can get thinner ones to fit.....