Vented Fore-ends?

[rckendall]

i shoot MR and LR F Class matches and three of my last rifles had vented Fore-ends, one with slots on the sides and bottom (Savage stock). We can shoot 25 rounds or so in 15 minutes and the barrels can get warm. There has been discussion on cooling the barrels after the fact, I wonder about helping them stay cooler, longer with these vents.

I am planning to fit a new stock to one of my rifles and it has no vents, so I ask, should I add some vents myself. It is a laminated stock. Does anyone cut bottom slots only?

Thanks for any input.

Richard

 

[Terry]

The Barrel Cool product works well.

http://barrelcool.com/product/barrelcool/

 

[rckendall]

I have one of those. I am interested in natural venting.

 

[dmoran]

You can mill all you want out of laminates, and basically every gunsmith worth a hoot can do it for you.
Biggest thing, use a spacious barrel channel, so it gets air freely to all sides of the barrel.

Good Luck

 

[dannyjbiggs]

i shoot MR and LR F Class matches and three of my last rifles had vented Fore-ends, one with slots on the sides and bottom (Savage stock). We can shoot 25 rounds or so in 15 minutes and the barrels can get warm. There has been discussion on cooling the barrels after the fact, I wonder about helping them stay cooler, longer with these vents.

I am planning to fit a new stock to one of my rifles and it has no vents, so I ask, should I add some vents myself. It is a laminated stock. Does anyone cut bottom slots only?

Thanks for any input.

Richard

For me, it makes more sense to have vent holes on the bottom of the forearm than side vents. All of my F-Class stocks, laminated, have 1/2 inch holes cut 2-inches apart throughout the bottom of the forearm...I cut them with a forester bit. Other than an aid to cooling, the holes offer a secondary aid for draining rainwater from the barrel channel when shooting in the rain.

Dan

 

[rckendall]

Thank you Donovan and Danny for your replies. I am trying to do my own stock work, hence my question and not just handing it over to my gunsmith.

I agree that giving the barrel lots of room for air to flow and the holes on the bottom are worthy suggestions. Also thanks for the sizing and spacing of the holes on the bottom Those are good guidelines and I will probably use them exactly.

Thanks again,
Richard

 

[Kings X]

I have been studying this for awhile.
The hot spot is where it should be - right at the throat of the chamber. Think of it as a “bulge “. So side vents cool the barrel in front of the bulge. Not good.
So a hole right through the stock from the bottom right at the bulge area provides the most air flow to remove the hot spot.
Barrel temperatures on my 284s go up 1-2 degrees per shot with normal vortex air flow via a 1” hole about 1-1/4” in front action.
The last couple years I have added a 12 volt mini fan the increase air flow. The latest trial in with a Chamber Chiller unit from Red River Reloading blowing in the hole. It runs off a USB power pack and has much more CFM air flow.
Remember that anything you add to the gun has to be weighted in before the match.

 

[Bart B.]

I've never had a barrel that moved bullet impact as it heated up firing every 20 to 30 seconds across 25 to 30 shots. That's with a 10 to 15 second chamber time per shot.

 

[dcali]

I would be surprised if they matter. During a string, there isn't sufficient time to significantly impact the temperature of the barrel, and afterwards, the rifle is typically stowed muzzle up with the bolt open, which seems like it would be a pretty good way to cool via natural convection. My rifle has vents, but I just like the way they look, and they won't hurt.

 

[rckendall]

I've never had a barrel that moved bullet impact as it heated up firing every 20 to 30 seconds across 25 to 30 shots. That's with a 10 to 15 second chamber time per shot.

So I take it that your stocks don’t have vents at all? I’ve heard it said by a well known stock maker that vents don’t do any good, they are just a visual preference. That may be very true. I’m still very new to this sport.

From a design and engineering standpoint, it seems that we should give every advantage, every place that we can. I will give the barrel some space for air to flow and enough vents to make me feel good, and certainly not compromise strength.

 

[rckendall]

I would be surprised if they matter. During a string, there isn't sufficient time to significantly impact the temperature of the barrel, and afterwards, the rifle is typically stowed muzzle up with the bolt open, which seems like it would be a pretty good way to cool via natural convection. My rifle has vents, but I just like the way they look, and they won't hurt.

At our club matches, between strings, we just slide our mats and gear back off the firing line so the next squad has room, and the rifles usually stay on the rest and bag. Because the sun/temperatures are hot much of the time, we try to shade the rifles and I do use a Barrel Cool device. But, I do want all the help I can get from natural cooling.

 

[Bart B.]

So I take it that your stocks don’t have vents at all?

You're right.

The range at Camp Perry, Ohio, has its safety zone north into Lake Erie. Boats in that area required a check fire on the firing line. I would come down a a click on the sight every 20 seconds on my 30 caliber magnums, 30 seconds with a 308. If shooting resumed before 20 minutes time, I would shoot to call with a hotter barrel. Then come up on the sight to zero for the rest. Never lost a point in elevation doing that.

A couple folks at Perry have shot most of a record breaking string but forgot to come down on their sight to compensate during a check fire. Their first shot upon resuming fire went out at 12 in the 9 ring.

But walking shots any direction as barrels heat up is a different problem.

 

[Kings X]

I would be surprised if they matter. During a string, there isn't sufficient time to significantly impact the temperature of the barrel, and afterwards, the rifle is typically stowed muzzle up with the bolt open, which seems like it would be a pretty good way to cool via natural convection. My rifle has vents, but I just like the way they look, and they won't hurt.

Do you plots your shots? I do and I saw my groups opening up towards the end of the 20 shot F Class string. I have heard the same complaint from other top notch shooters.
BART says he has never had a barrel that moved bullet impact as it heated up. With a 5” X ring at 1000 yards, any movement shows up. Now days Xs win.

 

[Bart B.]

With a 5” X ring at 1000 yards, any movement shows up. Now days Xs win.

Xes have always won, if they break ties.

A hundred years ago, before X rings, shots in the center half of the 10 ring were often called Fisher tens after Sgt. Morris Fisher USMC shot so many of them in international matches.

In one test of barrel heat, I put 30 shots from a 30-338 Mag inside 5" at 1000, about 20 seconds apart from an F class open position. Started with a cold barrel, random shot holes, no walking at all.

Square receiver faces typically fix this problem.

 

[dcali]

Do you plots your shots? I do and I saw my groups opening up towards the end of the 20 shot F Class string. I have heard the same complaint from other top notch shooters.
BART says he has never had a barrel that moved bullet impact as it heated up. With a 5” X ring at 1000 yards, any movement shows up. Now days Xs win.

I have not had groups open up with barrel temperature over 20 shots. But even if they did, cooling vents in the stock aren’t going to meaningfully change the barrel temperature while you are shooting.

 

[Kings X]

Thanks Bart, I didn’t know that about the Fishers. When I started in the 60s, we had Vs.
Knowing your gun, like the one you shot at Perry, is very important. On e-targets we can runs rounds down range every 4-5 seconds. Then stop for 10 minutes for the wind to “come back”. That next “ cold barrel” has to be right where you left off. But it is nice to have your other 30-338 threat you didn’t have to click every 20 seconds.

Damon, some folks believe that the barrel heats up during a string of fire. That’s where vents came from in the first place. Maybe they only help during “cool down” period after the match.
Here in Texas, we have a lot of programs that have 3 matches per day in tempatures around 100 degrees. With 3 relays, one relay shoots, then scores, then shoots again. There might be only 30 minutes for the barrel to cool down. Some shooters use addition methods to aid cooling - wiping down with ice water or alcohol. Others have a battery powered fans.
IMO I am sure that anything that opens the barrel to air is better than nothing.
Danny and I just believe that the rising heat off the barrel will drawn air up and around the barrel, if the stock has vents in the bottom. I just go one step farther, and add a fan.
Do any of the vents fix a problem we really don’t have? Probably not. So we are back to the “Cool Looking” factor.

 

[dcali]

They’re certainly not going to hurt anything. They may even help a little, but I wouldn’t spend a minute worrying about the difference. I bet a generous gap between barrel and stock does more.

 

[swd]

I like a slotted vent on the bottom of the fore end to let convection pull air through. It's not so much about stringing shots as helping the gun stay a little cooler and cool faster after the string. As in many parts of the country summers here can be over 100. When it's 105 the guns get hot and want to stay hot. F Open..

 

[Bart B.]

I bet a generous gap between barrel and stock does more.

The decades old standard is a dollar bill, .0043". But not in a shooting position.

That'll let most barrels touch the fore end from down pressure from ones cheek on a benched rifle on bags. Sometimes with only the weight of the rifle bending the fore end up. Measure your stuff to see.

15 to 20 bucks worth of dollar bills is better.

All barrels heat up across a string of shots. For example, 24 shots from 30 caliber service rifles in 50 seconds in some matches. They've left 2nd degree burns on folks.

 

[Bart B.]

With the cooling apparatus at matches becoming popular, the next one might be a cartridge machine giving each round the SAAMI twist before it's chambered.