Pedersoli Frontier/Blue Ridge Vent Liner hole size

[Critter Getter]

I have very limited flintlock experience and was just wondering if it is common practice to drill out the factory vent hole liner to 1/16? I don't really know what size the hole is from the factory or if I would notice any improvement by drilling it out. I don't really think the ignition is slow but honestly don't know since I am not around other flint rifles to compare it to. I am the type that sides toward the "if it's not broken...don't fix it!" Greg.

 

[Zonie]

Go ahead and "fix" it.

As I mentioned on other posts, the Italians always seem to drill their vent holes too small. I don't know why.

This always seems to make the guns fire slowly or not at all even though the powder in the pan flashes just fine.

Flintlocks are sometimes fussy about their loading and priming but if everything is "right" you'll be surprised at how fast they fire.

Pletch has measured the ignition speed of many flintlocks and has proven that flintlocks, even if everything is perfect, are slower than the percussion fired guns.

How much slower? Often the difference is in thousandths of a second. Much too small to be sensed by a human.

On the other hand, it is not uncommon for there to be a noticeable delay between the falling of the **** and the firing of the gun.

Because of this it is important to hold the sight on the target without flinching or changing your hold until the fun fires.

I try to hold it on target for a count of one after it fires.

This "follow thru" will become a habit after shooting flintlocks for a while and I guarantee it will carry over to all of your shooting.

When it does, all of your shooting will improve greatly.

 

[Larry Pletcher]

Opening a vent to 1/16" is a very common change. Jim Chambers sells his liners with a .055" hole. He figures that if he ships them under size the consumer can always make them larger, but you can't make them smaller. I drill mine with a 1/16" bit to start with. I sometimes go to a numbered bit larger. In many cases 1/16" works fine. If a larger hole seems necessary I would enlarge gradually using numbered bits. There are 5 numbered bits available between 1/16" and 5/64", and 5/64" is way too big.

#52 is .064
#51 is .067
#50 is .070 (borderline too big IMHO)
#49 is .073 (don't like to go this big)
#48 is .076 (if this is necessary something else is wrong)

Either #52 or #51 will allow a pipe cleaner to be used to make sure the vent is clear. Clean is VERY important; maybe more important than vent size.

One last comment -- In my last build, I drilled the vent and sighted the gun in. It was shooting very well. I thought that the #52 bit (.064) was working very well. Just to check I grabbed a #52 and it wouldn't go in. I had drilled with a 1/16" (.0625) and it was working fine.

Regards,
Pletch

PS make sure you have priming powder up against the barrel. The closer the fire the hotter it is.

 

[Critter Getter]

Thanks Guys! I will take your advise and run with it. I appreciate all your help! Greg.

 

[Britsmoothy]

I opened my pedersoli trade gun liners hole and gained much better ignition.

B.

 

[bpd303]

My 54 caliber Blue Ridge came from the factory with a 1/16th flash hole. Very reliable.

 

[marsh trapper]

I drilled mine to 1/16 on my frontier pedersoli says there 1/16 touchholes stock but there not...after drilling mine ignition improved dramaticly

 

[Critter Getter]

Well I just took a 1/16" drill bit and slipped it right in to my flash hole. Straight from the factory that way so I'm going to leave it alone! Thanks for all the info and help fellas!! Greg

 

[Billnpatti]

I always open the touch hole to 1/16 inch. Then I take a bit about 3/16 and twist it by hand to cone the hole.

 

[AZbpBurner]

I've opened up all my Lyman rifle touch holes to .064" with a #52 bit. Makes a big difference, too when the inside of the liner hole is chamfered or 'coned'.

 

[Robert Wilson]

Inspired by this, and other, recent posts, I picked up a couple of 1/16" drill bits. I wanted to use one to check the diameter of the flash hole on the coned insert my gunsmith installed in my Lyman GPR. He converted it from a percussion to a flint lock, at my request, and installed an L&R repacement lock.

As I suspected, the flash hole was less than 1/16" and it was a small matter to carefully open it up with a small hand drill. I look forward to trying the new, larger, flash hole this Tuesday, at the range.

I've always enjoyed this rifle, and it has taught me a lot. When I had a few too many FTF's, I first concentrated on learning more about flints and frizzens, and soon graduated to "flashes in the pan". I noticed that I had to fill my pan right up to the brim, every time, for reliable ignition, and some ignitions were slower than others. (The flash hole is positioned almost perfectly, in the "sunset" position.)

It wasn't until I joined this forum and got the benefit of a whole lot of practical experience, that I even considered the size of the flash hole as a potential cause of my rifle's apparent lack of reliability. You folks make me smarter by the day, and I am grateful...

 

[Critter Getter]

Let me know if you notice any improvement when you head to the range Tuesday. Inquiring minds want to know! Greg.

 

[BigBoreBLR]

Bigger holes loose velocity.

too small of a hole and you don't get any velocity.

1/16" is perfect with what I shoot.

I also took a 1/4" drill bit and cones the face of the hole slighty. Kind of like using a funnel to pour oil into and engine idea. Not too big of a funnel face, you loose space for a screwdriver to grab the bit.

The hole size only does so much for speed.

Keep the pan real clean, the bottom face of the frizzen clean and shiny to reflect the heat into the pan, keeping the flashhole clear. Putting enough, but not too much powder in the pan. Having good reliable spark with the right flint to frizzen gap and good flints. This stuff matters more than the hole size.

If you do all that and still seem to have reliability problems, then open the hole a bit. However, I may be tempted to blindly bring it out to 1/16ths anyway. Or maybe use numbered drill bits and drill it out between what you got now and 1/16".

How well do you shoot offhand at 50 yards.

If you can barely notice a delay at all, or don't notice one, then gun is working fine.

Most ignition problems are solved by better cleaning of the pan and flashhole between shots.

 

[BigBoreBLR]

A big one.....

Make sure your powder in the pan is not blocking the flash hole. That is when you get real slow ignition problems.

I keep trying less powder in the pan until I find out how much is really too little.

I bring a rag with me, wipe the pan clean, wipe the frizzen clean, pick the flash hole good, then put powder in when I am ready to shoot again.

I also let the gun stand for a few days with the muzzle pointing down to let any cleaning or storage oils drip out of the barrel and not into the pan, frizzen, or breech areas.

Keep that pan powder fresh when hunting. I change mine out every hour when on foot or sitting in the open by a tree. Or leave the gun powder less in the pan with a feather in it when stand hunting.

 

[Critter Getter]

Thanks for all the good advise. I do wipe clean the frizzen and the pan between shots. I really do not believe that I have any ignition problems and my gun is indeed very reliable. My shooting on the other hand........ Not so good. I shoot at 50 yards off hand with my Hatfields and TC percussion guns. Those all shoot extremely well. ( not uncommon to shoot 3 shots touching). My flintlock however I may get lucky to shoot 3-6 inch groups and have been known to fling some flyers off a 4 foot piece of cardboard!! . Well most the time I can keep them on the cardboard!!!! . I'm sure as I shoot more and work on my follow through I will learn to shoot this correctly! I have only got maybe 60 shots through this rifle and understand there is a break end period to be expected on most of these Italian guns. I'm sure the biggest factor in all if this is the Jerk on the trigger..... ME! . Thanks again. Greg.

 

[bpd303]

Ah, the infamous flintlock flinch. It will disappear if you concentrate on the front sight & target. I hold on target for the count of two after the boom.

 

[TMan51]

My CVA Flint Mountain Rifle wasn't bad, but it wasn't great either. I used it in PA for several seasons, and managed a few, when it went off, and quite a few when it didn't.

So I started getting serious about making it more reliable. The 1/16" hole definitely helped, as the CVA flash hole was smaller than that. I pulled the lock apart, polished it up, and lock time was faster, no doubt. I hardened the frizzen, and picked up several flints from TOTW, yep, that made a difference. Thanks Peter Alexander.

After hooking up with this forum quite recently, I polished the pan, for about two hours, with 2K grit Emory, and Dremmeled the pan to put the hole a bit above the flash. Then I put a cone on the liner with a tiny Dremel grinder bit. Now that made a difference. I was out today in the 18 degree snow and wind, as I'm now 6 days retired and can do what I want, and I had 100% ignition for 12 shots, when I started to get solid and left.

I'm thinking, maybe these guys know their stuff.

 

[Zonie]

Small changes in the vent hole size can make a lot of impact on how well a flintlock fires.

This is due to the fact that small changes in size makes for a big change in the area of the hole.

Larger size areas let in a larger amount of the pans priming flash.

Using standard Metric drill sizes I see that a 1.4 mm drill is .0551 inches. That seems to be about the size many of the Italian guns come with.

A .0551 diameter hole has a area of .0024 square inches.
Drilling this hole out using a 1/16 inch drill bit changes the hole size to .0625 inches.

That .0074 inch size increase changes the size 13.4 percent but it changes the surface area of the hole 29 percent.

That's almost 30 percent more heat coming thru the flash hole.

Drilling the original metric hole using a #51 drill bit (.0670 inches) would increase the surface area of the hole 47.9 percent.

That's almost a 50 percent increase!!

No wonder drilling the vent hole helps to reduce the number of misfires.

IMO, although the increased area of the vent hole will allow more powder gas to escape, in all but the .32 caliber this won't effect the velocity of the projectile much, if at all.
Adding another grain of powder will more than make up for the loss.

Besides that, if the gun is sighted in with the increased vent hole diameter existing, the sighting in process will take care of any velocity that is lost thru the vent.

 

[Robert Wilson]

Yup! I increased the size of the vent to 1/16", and took my Lyman GPR to the Range today. (I will not describe the range conditions, out of respect for the sensetivities of my northern brothers.) I could not have been more pleased.

Critter Getter: Since you asked, I am pleased to report that my flintlock fired every time! There was also, as far as I could tell, a definite increase in the speed of ignition. I am a VERY happy camper!

Zonie and Pletch: You have both been elevated to my short list of muzzleloading heroes! Gentleman, your willingness to share your expertise with new guys could not have been more specific and more useful. Thank you both, for making a very serious improvement to my "quality of life"!!!

Many, many thanks,
Bob

 

[Twowithone]

Congrats on your retirement. :thumbsup: