You can relax, it's normal.

 

Thanks, good to hear this is not a defect but it does seem odd. Do you have any ideal why Beretta would not make the gas port hole the same size all the way through? It takes a fairly complex separate machining operation to make the hole 2 different sizes and I cannot think of any advantage. Every gun I have seen has the gas ports the same size all the way through, including my 391s.

Anybody else have an explanation? It is easy to test, just pull the piston out of the gas cylinder on the barrel and stick a 1/8" drill bit into the gas port hole that goes through into the bore. On my gun the 1/8" bit will not go through but a 7/64" bit does go through. How can this lip help, why not just make the hole 1/8" all the way though?

Seems to me that the lip will create turbulence as the combustion gas enters the hole and it definitely restricts gas flow which makes the gun less able to cycle light target loads. Failure to cycle light target loads is a common complaint so the lip does not seem like a good idea for a clay target gun like the Excel.

 

Yes, that is odd, but really no odder than having a second gas port that doesn't go all the way through.

I don't know, but I think I read somewhere that the early A400s had the second "blind" gas port, but later ones do not.

My guess is, when Beretta first put the model in production, they were afraid that after some experience by actual customers, they might need to enlarge the gas ports to make the guns handle lighter loads. If they suspected a need for that, they might have included a blind port and a stepped port to make it easier to do the modification.

Nobody knows what goes on in the mind of Beretta - they do some strange things. I'm just guessing, but that's my story and I'm sticking to it! :lol:

 

I thought it had something to do with bleeding off excess gas pressure??

 

My understanding as well and is (as I understood it) the reason my A400 Xcel can shoot anything from my light 3/4oz reloads up to 3" boomers without changing or adjusting anything.

 

My understanding as well and is (as I understood it) the reason my A400 Xcel can shoot anything from my light 3/4oz reloads up to 3" boomers without changing or adjusting anything.

But why would Beretta setup the Xcel (a target gun) so it can shoot 3" boomers?? Why not set it up for target shooters who don't use anything more than standard 2.75" 1.125oz target loads but many of us shoot mostly 3/4oz super light loads to save money and reduce recoil.

My Xcel will cycle my 7/8oz 1200fps reloads perfectly and lock the slide back on the last shot every time. It will also cycle (meaning shoot 2 shots in a row) my 3/4oz 1250fps practice loads fine, but will not lock the slide back on the last shot every time, maybe 50% of the time. My gun only has about 400 bullets through it and my recipe for 3/4oz is real light - 15gn Extralite, CB0175 wad, Fio primer, GunClub hulls. So maybe it will get better with more break-in time.

But my 391s cycled and locked the slide back every time with those same 3/4oz reloads right from the first shot. Thus the A400 is more finicky, why would Beretta do this? Very strange to me.

 

My understanding as well and is (as I understood it) the reason my A400 Xcel can shoot anything from my light 3/4oz reloads up to 3" boomers without changing or adjusting anything.

But why would Beretta setup the Xcel (a target gun) so it can shoot 3" boomers?? Why not set it up for target shooters who don't use anything more than standard 2.75" 1.125oz target loads but many of us shoot mostly 3/4oz super light loads to save money and reduce recoil.

My Xcel will cycle my 7/8oz 1200fps reloads perfectly and lock the slide back on the last shot every time. It will also cycle (meaning shoot 2 shots in a row) my 3/4oz 1250fps practice loads fine, but will not lock the slide back on the last shot every time, maybe 50% of the time. My gun only has about 400 bullets through it and my recipe for 3/4oz is real light - 15gn Extralite, CB0175 wad, Fio primer, GunClub hulls. So maybe it will get better with more break-in time.

But my 391s cycled and locked the slide back every time with those same 3/4oz reloads right from the first shot. Thus the A400 is more finicky, why would Beretta do this? Very strange to me.

Not enough pressure?
Try a different powder that has a higher PSI.
Clean gun again, lube bolt and rails.

 

I thought it had something to do with bleeding off excess gas pressure??

I don't have the target model, have the Action model. In mine, there is one port from the barrel and an array of ports around the back end of the gas chamber to bleed off gas through a spring loaded normal closed valve (collar) and out the bottom of the forearm stock.

 

I suspect the XScel has a 3" design as a cost savings - the only difference between most models' receivers seems to be the color

 

I suspect the XScel has a 3" design as a cost savings - the only difference between most models' receivers seems to be the color

Xcel is heavier.

 

Every one i have seen is set up this way

 

My understanding as well and is (as I understood it) the reason my A400 Xcel can shoot anything from my light 3/4oz reloads up to 3" boomers without changing or adjusting anything.

Would you mind telling us your 3/4oz recipe?
My A400 would not reliably cycle my 3/4oz reloads (15gn Extralite, CB0175 wad) especially after I had shot about 100 rounds but it cycled 7/8oz reloads perfectly. Other A400s I have tested or heard about also fail the 3/4oz test. I don't want to use more powder or a different powder since my recipe performs perfectly on targets and keeps cost low. I shoot a lot and cheap ammo is important.
I cured my problem by drilling out the single gas port to .135", the gun now cycles 3/4oz and heavier target loads flawlessly.
I still amazes me that Beretta does not offer target models like the Xcel with 2 3/4" chambers and with both gas ports open like the 391s and prior models.

 

My understanding as well and is (as I understood it) the reason my A400 Xcel can shoot anything from my light 3/4oz reloads up to 3" boomers without changing or adjusting anything.

Would you mind telling us your 3/4oz recipe?
My A400 would not reliably cycle my 3/4oz reloads (15gn Extralite, CB0175 wad) especially after I had shot about 100 rounds but it cycled 7/8oz reloads perfectly. Other A400s I have tested or heard about also fail the 3/4oz test. I don't want to use more powder or a different powder since my recipe performs perfectly on targets and keeps cost low. I shoot a lot and cheap ammo is important.
I cured my problem by drilling out the single gas port to .135", the gun now cycles 3/4oz and heavier target loads flawlessly.
I still amazes me that Beretta does not offer target models like the Xcel with 2 3/4" chambers and with both gas ports open like the 391s and prior models.

You just voided the warranty by doing that so you can shoot 3/4 oz loads. :roll:

 

15 grains of extra light is right on the edge in getting the A400s to cycle reliably with 3/4 ounce loads. My a400 Unico will cycle 15 grains but not lock the bolt open and many others I have sold have been the same. Of course mine has about 20,000 rounds through it. If you step up to 16 grains or even to 16.5 you will get much more reliable ejection and better patterns also. Unfortunately, every gun design has a minimum requirement for reliable ejection and it isn't the same for all models or even within models. My personal 391 will cycle 15 grains but my rental 391 gold target will not. That said, I can tune either one to do what I want with different exhaust valve springs or even shimming the existing spring.
One thing that you will want to watch for now is bolt speed with heavier loads. You have in effect tuned your gun to shoot a very light load but the flip side of that is putting too much gas through the system and damaging the receiver or other components due to excessive bolt speed or exhaust gas. The design of beretta's exhaust system will likely make this a moot point but it is something to be aware of. I have recently been seeing some peening in a400 action models that have shot nothing but light target shells. Perhaps they aren't exhausting enough gas. The peening is fairly minor but to me suggests gas flow could be on the high side for the few I have looked at.
Another thing to be aware of is the A400s need a lot of break in. Not just 4-5 boxes but 4-5 flats to loosen the gun up. They tend to cycle better and be more forgiving with some wear.
I have an A300 that I actually reamed the extra blind port open. It was a rental so I decided to experiment. Then Cole's replaced the piston stop and forearm on the gun shortly thereafter, (Under Warranty). The latter had more to do with initial teething problems but that extra exhaust gas has to go somewhere. As it is a rental gun that doesn't see any hot loads, it has been very reliable since but still does not like to go below 7/8s oz loads and be reliable off of a kids shoulder. Just my 2 cents.

 

My understanding as well and is (as I understood it) the reason my A400 Xcel can shoot anything from my light 3/4oz reloads up to 3" boomers without changing or adjusting anything.

Would you mind telling us your 3/4oz recipe?
My A400 would not reliably cycle my 3/4oz reloads (15gn Extralite, CB0175 wad) especially after I had shot about 100 rounds but it cycled 7/8oz reloads perfectly. Other A400s I have tested or heard about also fail the 3/4oz test. I don't want to use more powder or a different powder since my recipe performs perfectly on targets and keeps cost low. I shoot a lot and cheap ammo is important.
I cured my problem by drilling out the single gas port to .135", the gun now cycles 3/4oz and heavier target loads flawlessly.
I still amazes me that Beretta does not offer target models like the Xcel with 2 3/4" chambers and with both gas ports open like the 391s and prior models.

MY recipe is Rem GC hull, Fiocchi 616, CB 3/4oz wad and 17 of Titewad for a chrono reading (at 5') of 1210 avg with a low of 1205 and a high of 1215

 

Oneounceload and Turpentine,

Thanks to both of you for the info, very helpful. Now I see why Oneounceload's guns cycle 3/4oz reloads, he is using 2gn more powder than me! I am shooting about 30k bullets a year so that 2gn difference adds up.

I know I could increase my powder charge but refuse to due to increased cost of ammo and, more importantly, the absolutely outstanding performance I get from my current recipe with only 15gn. I know some people report that higher velocity improves patterns but my tests do not confirm that. My reloads pattern super well and I would not want to mess with that result.

As to wearing the gun in, I basically do that before even shooting it. I disassembe the gun completely and clean, debur and polish all the moving parts. Then I shoot about 6 boxes thru the gun and examine the wear marks, and repolish as necessary and repeat that process several times until the gun operates smooth as butter, very much like a gun with 20k rounds thru it but with less actual wear. I have 40k rounds thru 2 391s that had this treatment and the main moving parts show no wear using a dial caliper that measures to .0005. So my gun was not struggling with the light 3/4oz reloads due to the gun being new, just a lack of gas pressure.

I will never shoot anything thru the A400 heavier than 7/8oz 1250fps reloads so increased bolt speed is not an issue for me. But I am certain it will also handle continuous use of 1oz and 1.125oz factory target loads as well. As Oneounceload pointed out the gun is setup to handle 3" boomers so increasing the gas port size a few thousandths is not going to affect ordinary target loads.

Not sure what you mean by this statement: "I have recently been seeing some peening in a400 action models that have shot nothing but light target shells." Where is the peening? I never saw an Explor Action model, is anything different from the Xcel?

For Dr Duk - luckily I do my own gunsmithing so I am not worried about any warranty. Would not trust Beretta with my guns and from what I hear their warranty service is not the most customer friendly. If I had an issue that was over my head I would send the gun to Cole's or Bill Skinner, not Beretta.

 

The peening is at the very rear of the receiver. The bolt is actually slamming into the back of the receiver with enough force to overcome the bolt buffer. The action is the 3" field version in the wood a400 line. The receiver is bronze in color. Some of my you shooters are using them for clays due to the fact that they are lighter than the xcel. I actually use an xplor unico for my clays gun. It is a 3.5" gun that I have customized for clays. It has the green receiver. The bolt buffer on the xplor upon examination appears to have more travel than the " a400 action" buffer has. This gives it more time and distance to slow the bolt and in effect reduce the possibility of damage to the rear of the receiver due to excessive bolt speed. The peening leads me to believe that perhaps the Action is slightly over gassed which I intend to speak to Beretta about. I have not examined the xcels buffer yet for comparison. If you always intend to stick to light loads you absolutely did the right thing. I do wish the a400s would allow the user to make adjustments to the exhaust valve spring much like the 391's did. That would make for a much more forgiving and less permanent method of tuning. I completely understand you wanting to stay as economical with your powder drops as possible. I do the same thing as do most reloaders I know. But the extra reliability I get from a one grain increase of xtra lite, along with better target breaks, was a better solution for me. I do go lighter sometimes however and sub a federal primer into the mix. Anything below 16 grains in a 3/4 load in my gun gives a very core heavy pattern regardless of choke. Basically, there is no fringe at all!
You obviously know more about your guns than the average shooter if you are de burring and polishing your guns moving parts. Many of the folks that come into my shop bring their gun in in a box of loose parts after trying to clean or fix it themselves. I apologize if my first post offended you.

 

My Excel is peening the back or the receiver as Turpentine describes. I use 3 dram 11/8 loads.

 

The peening is at the very rear of the receiver. The bolt is actually slamming into the back of the receiver with enough force to overcome the bolt buffer. The action is the 3" field version in the wood a400 line. The receiver is bronze in color. Some of my you shooters are using them for clays due to the fact that they are lighter than the xcel. I actually use an xplor unico for my clays gun. It is a 3.5" gun that I have customized for clays. It has the green receiver. The bolt buffer on the xplor upon examination appears to have more travel than the " a400 action" buffer has. This gives it more time and distance to slow the bolt and in effect reduce the possibility of damage to the rear of the receiver due to excessive bolt speed. The peening leads me to believe that perhaps the Action is slightly over gassed which I intend to speak to Beretta about. I have not examined the xcels buffer yet for comparison. If you always intend to stick to light loads you absolutely did the right thing. I do wish the a400s would allow the user to make adjustments to the exhaust valve spring much like the 391's did. That would make for a much more forgiving and less permanent method of tuning. I completely understand you wanting to stay as economical with your powder drops as possible. I do the same thing as do most reloaders I know. But the extra reliability I get from a one grain increase of xtra lite, along with better target breaks, was a better solution for me. I do go lighter sometimes however and sub a federal primer into the mix. Anything below 16 grains in a 3/4 load in my gun gives a very core heavy pattern regardless of choke. Basically, there is no fringe at all!
You obviously know more about your guns than the average shooter if you are de burring and polishing your guns moving parts. Many of the folks that come into my shop bring their gun in in a box of loose parts after trying to clean or fix it themselves. I apologize if my first post offended you.

Turp,

Absolutley no apology necesary, you were being helpful and I really appreciate it. I love it when people point out potential issues, helps me re-think my ideas and confirm them or change my opinion. I don't like having incorrect information so feel free to educate me or challenge anything I say.

I am amazed to hear that the bolt on the Action model is slamming into the buffer hard enough to overcome it using target loads. My buffer tip sticks out about 3/16" of an inch and I cannot compress it fully even pushing on it as hard as I can with a big dowel. I did shoot a couple of boxes of factory Federal 1.125oz target loads for breakin purposes and I did not feel the bolt bottoming out or see any peening whatsoever. Only have about 1k rounds thru the A400 so far total and that buffer is still pristene.

I agree that adjustable spring tuning is way better than drilling out gas ports and I was not too happy that my new A400 would not cycle 3/4oz when both of my 391s did so perfectly right out of the box. Don't understand why Beretta did not use the same double gas ports and changeable spring method instead of giving us one tiny gas port that is really only necessary if we shoot big boomers. Target shooters do not need heavy loads and we shoot the most ammo so why not set the target guns up accordingly and let hunters buy the models designed for heavy stuff.

I am aware that many guys like more powder than I use for 3/4oz but my super light load performs fabulously well in both of my 391s and the A400 (now that it cycles properly) and saves money so I am sticking with it.

Thanks again.

 

Don't understand why Beretta did not use the same double gas ports and changeable spring method instead of ...

Actually, Beretta did not use the changeable spring method in the A390 and A391, either. That was an aftermarket innovation by Cole Gunsmithing.

 

Don't understand why Beretta did not use the same double gas ports and changeable spring method instead of ...

Actually, Beretta did not use the changeable spring method in the A390 and A391, either. That was an aftermarket innovation by Cole Gunsmithing.

Yes, you are correct, I should have said it that way. I was agreeing with Turp that tuning for light or heavy loads using different springs is better than having to drill holes in your gun.

 

I would like to note some cautions about drilling out gas ports for others who might try this in order to get their A400 Xcel, or comparable target model, to cycle very light target loads:

My A400 Xcel's gas port opening near the bore was about 7/64ths (.1094") in diameter from the factory. But this port quickly opens up to about 1/8" (.125") for most of the length of the port, thus there is a short taper or lip in the port nearest the bore itself. The other port hole which is also about .125" in diameter is not drilled all the way thru.

I first drilled the lip or taper out of the open port by drilling it out with a 1/8" carbide bit and tested this with my 3/4oz and 7/8oz reloads. There was no difference from the factory port size - the 7/8oz reloads cycled perfectly, 3/4oz reloads did not (meaning at first when the gun was super clean they would usually fire 2 shots in a row but would not always lock the slide back on the last shot and after about 100-125 rounds most would not even eject from the gun let alone fire 2 shots or lock the slide back).

Next I drilled out the 1/8" hole with a .135" carbide bit. This completely cured my cycling problems and now the 3/4oz reloads always fire 2 shots in a row and always lock the slide back after the last shot, or a single shot. This test involved about 400 rounds so I am very sure the new .135" gas port solves the cycling 3/4oz reloads problem completely. I also fired at least 200 7/8oz reloads and they continue to cycle perfectly and lock the slide back.

There are several cautions.

1) My main caution is that this procedure only applies, as far as I am concerned, to cycling very light 3/4oz reloads. If you don't shoot very light 3/4oz shells you don't need to drill your port holes. Oneounceload and others report that their A400s do cycle 3/4oz shells just fine without drilling (they all probably use more powder in their recipe than me). In my opinion, if your A400 will not cycle 7/8oz or larger reloads then something else other than gas port size is wrong. Any A400 target gun should easily cycle 7/8oz, 1200fps reloads without any modification assuming the gun is reasonably clean and broken-in.

2) Be careful drilling out gas ports, it is very easy to snap a bit off and get it stuck in the port hole. I clamped the barrel in a padded vice, used lots of light and held my cordless drill as solid as I could so I could keep the bit going in straight. Drilling out the lip with the .125" bit was very easy since the existing hole guided the bit straight. But drilling out the .125" hole to .135" required much more care to keep the drill bit going straight. If the bit snaps off and gets stuck solidly in the gas port, you have a big problem, so be careful. It would be best to give this job to a gunsmith unless you are sure of your skills.

3) Don't be tempted to drill out the second (blind) gas port instead of making the existing port bigger. The reason is that drilling out the second port would probably make the gas flow too great and probably be dangerous!! My gun now cycles super light 3/4oz reloads perfectly with the single gas port .135" in diameter. I only increased the factory gas port from .1094" to .135", a total increase in diameter of .0256". That's only 25 thousandths. The smallest drill bit in my drill set is 1/16" (.0625"), that's 62 thousandths, over double the amount of increase that I used. So even if you used that tiny bit to drill out the second port, it might cause too much gas flow. Plus I doubt you could drill a hole that small (1/16") without breaking off the drill bit because bits that small are flimsy and anything bigger increases the risk of too much gas flow.

4) It is possible that increasing the size of the single gas port to .135" will cause firing heavy hunting type loads to bottom out the bolt buffer in the back of the receiver which could cause peening or other damage to the buffer and the bolt. I doubt that would happen and, personally, I would not use a target gun for heavy hunting loads but it is a factor that should be considered before drilling out the gas port.

5) Drilling out gas ports undoubtedly voids your warranty. Not an issue for me but might be for others.

 

I was watching this thread because my A400 is not cycling Remington Sport 1 ounce @1145fps loads. Coles had mentioned that they have a stiffer gas valve spring that might help with the problem. So perhaps an alternative to opening gas ports is making it harder for the excess gas to bleed off by using a heavier spring.

 

Chris, I seriously doubt that a stiffer spring will help because there is probably little or no gas bleeding off with the factory spring (the factory spring is stiff and setup to bleed excess gas off from heavy loads, not light target loads like you are using) and a 1oz 1145fps factory shell would certainly provide enough gas pressure to cycle an A400 in good operating order.

I would need a lot more info about your gun to know why you are having cycling problems. I don't do gunsmithing for other shooters but the few autos I have examined that are not cycling standard factory loads have something else wrong with them, generally they are too dirty or have damaged parts usually due to lack of proper cleaning/lube. On the A400 I have seen the bolt hang up due to the breech bolt pin (which acts as a cam to rotate the bolt as it goes into battery) becoming peened and due to the extractor cutting a groove in the barrel ramp as the bolt goes into/out of battery. Both of these conditions make it harder for the action to cycle. Replacing the breech bolt pin, reshaping the extractor face, smoothing the barrel ramp and polishing all these mating surfaces really helps.

To test for proper cycling, I remove the recoil spring, put the bolt assembly and barrel (not the trigger) back in the gun and cycle the action by hand to feel for smoothness and any binding. The action should open and close fully into/out of battery with zero restriction or binding. Then put the trigger assembly back in the gun and again cycle the action by hand. There will now be considerable restriction from the springs in the trigger assembly rubbing on the bolt assembly parts but this restriction should still be smooth and allow easy cycling by hand. Unfortunately, it takes experience to know what "feel" is proper compared to excess binding. If you have access to another A400 that is working properly, it really helps to compare the 2 guns side by side to see and feel for any differences in how the actions cycle by hand and what the various parts look like side by side.

Probably the best idea is to get the gun to Coles and let them examine it and fix it up.

 

William, thanks for the tips. My gun has very few rounds through it. I am the second owner, but I know the first one (a SGW member) barely put any through. In addition, Beretta replaced the factory barrel because the original had a defect (gouge in the chamber). I followed your instructions. With the trigger group and recoil spring out of the gun, the bolt cycled very smoothly. I put the trigger unit back in a d the cycling was considerably harder towards the rear part of the travel, when it encountered the spring resistance.
The only real wear I see in the gun is two spots where the receiver mates with the barrel extension. One spot is from the ejector and the other is maybe from a roll pin below it that keeps it in place.
I took some pictures in case that might be of help.