2500X / BnA trigger question

[cavedweller60]

Has, or does, anyone use the shorter pin fall set up on a BnA / 2500X combo? If so, how did it work and did you stick with it?

 

[cavedweller60]

Has, or does, anyone use the shorter pin fall set up on a BnA / 2500X combo? If so, how did it work and did you stick with it?

I expected some responses so, maybe I asked the wrong question or, the right question the wrong way.

Let's try this a different way. Has anyone played around with flipping the 2500X trigger hanger to get the shorter strike? If so, what did you find? Did it work ok? Are you still doing it?

I am struggling to get my rifle to shoot. I have tried several different ammo types and nothing seems to help. In examining the empty cases, the pin strike seems very hard. It also, compared to the guy shooting next to me, went quite far in from the case rim. I was thinking about flipping the hanger to lighten the strike.

 

[tmwinds]

Have you measured the firing pin protrusion and is it excessive? I believe the protrusion should be around.025 minimum and .035 maximum.

 

[padom]

I have not changed anything on my BNA Competition trigger and 2500x setup and my rifle shoots excellent.

 

[cavedweller60]

Have you measured the firing pin protrusion and is it excessive? I believe the protrusion should be around.025 minimum and .035 maximum.

Thanks for the response. The protrusion is .030 +/- a thou so, it sounds within spec. I should be clear. It shoots ok but, I've spent many hours over the last 3 days shooting multiple different varieties of ammo and going up and down the tuner and can't find a reliable node...or even a reliable pattern in the groups. I compared 6-8 fired cases with the guy sitting next to me and the difference in strike is night and day so I began wondering if flipping the hanger might be something to try.

 

[Greg Brooks]

You want the dimple in the hanger pointed forward toward the barrel. I would advise against using it at the rear unless there are issues, to over come with your sear/cocking piece interface - (ie sombody ground on the trigger sear shortening the length of it etc.) You can trim a coil off the .055” spring to try and get to around .016” to .020” pin indentation.

 

[TRSR8]

Probably ill advised to swap hanger, and by no means touch the FP, Jerry has them just fine.
Get 1-2 extra springs( they’re cheap) and in the mean time, take about 1 1/2 coils off yours if it’s OEM.
If not mistaken Stiller trims them like this on his personal guns…you want full travel/less force.

 

[dhenry132]

Little hole on the hanger to the front, towards barrel.
I ran B’A for about 3 years and around 30K rounds without any problems.

 

[tmwinds]

Thanks for the response. The protrusion is .030 +/- a thou so, it sounds within spec. I should be clear. It shoots ok but, I've spent many hours over the last 3 days shooting multiple different varieties of ammo and going up and down the tuner and can't find a reliable node...or even a reliable pattern in the groups. I compared 6-8 fired cases with the guy sitting next to me and the difference in strike is night and day so I began wondering if flipping the hanger might be something to try.

It sounds like the firing pin protrusion is just about perfect. That leaves the spring. Maybe order a new spring and trim the old one.

 

[padom]

It sounds like the firing pin protrusion is just about perfect. That leaves the spring. Maybe order a new spring and trim the old one.

What ammo are you shooting that you think you have a firing pin/ignition problem? How many lots did you test?

 

[cavedweller60]

What ammo are you shooting that you think you have a firing pin/ignition problem? How many lots did you test?

I don't think I have a firing pin / ignition problem but, I do see a huge difference in the primer strikes I am getting compared to what I saw from another shooters casings. I am struggling to get consistency out of the rifle and I am exploring things that can cause erratic results but that, don't require anything extreme to fix / check. I can flip the hanger around and obviously, it isn't doing anything that can't be easily reversed.

I tried 3 lots of center x, two lots of Eley match and 1 lot of tenex and non of them give consistent repeatable results. In looking at the spent casings, the firing pin is hitting hard enough to make an apparent deformity to the rim of the spent casing. The center x is also showing a bulge in the center of the spent casing which I have never seen before on any of my rimfire guns.

Here are a couple pictures....

You can see the little bulge in the center and the difformity of the rim. Maybe this is completley normal but, I can say I sifted through the empty brass buckets looking at brass and I looked at a bunch of casings from the guy shooting next to me and I didn't see any other Lapua ammo with a similar bulge. Like I said, it might be completely normal. If I had seen it on one lot of CX I would wonder if it was an ammo issue but, it happened to 3 different lots.

I don't know if there is an issue, I am asking questions in an effort to try and find a path forward.

 

[TRSR8]

Your hit is not excessively deep but I’d go with the spring trim.
If you know what you’re doing you might also give the pin tip a bit of angle to bring it in from the rim a bit.
Al this said, still more than a few variables, you may be dealing with a ho hum barrel,you may not be ideally maintaining it, etc., etc.

 

[cavedweller60]

Your hit is not excessively deep but I’d go with the spring trim.
If you know what you’re doing you might also give the pin tip a bit of angle to bring it in from the rim a bit.
Al this said, still more than a few variables, you may be dealing with a ho hum barrel,you may not be ideally maintaining it, etc., etc.

Have you ever noticed that bulge in the center of the head? You can almost tell in the second picture but, it almost looks like the center of the case head is being plowed up by the strike.

 

[TRSR8]

Have you ever noticed that bulge in the center of the head?

Me, I have not, however, from the lateral image no obvious bulge I can see.
i guess my first question would be what’s your headspace, who fit the barrel?
The other thing is, what kind of scores does this thing shoot, since you really have not indicated. If it’s laying down solid scores….everything is far less important.

 

[cavedweller60]

Me, I have not, however, from the lateral image no obvious bulge I can see.
i guess my first question would be what’s your headspace, who fit the barrel?
The other thing is, what kind of scores does this thing shoot, since you really have not indicated. If it’s laying down solid scores….everything is far less important.

That's the problem, it is new...probably 1000 rounds through it.

I've spent most of the time trying to tune it and there is just no repeatability I can find. I spent about 4 hours yesterday on a cool foggy day because it was as close to zero wind I've seen since I got it. Out of around 125 3 shot groups, I might have had 20 in which all 3 shots were touching.

There was no tight / wide pattern, as I've seen in my other gun, as I moved through the tuner. On the few decent groups I had, I would shoot 5 shot groups on each side of the node to try and tighten them up more and the groups were not repeatable. I've only shot a couple full cards with it and it is shooting 2150ish for scores. That being said, I sat down with my old gun and shot a 2250 on a lesser rest, when I started getting frustrated with tuning.

It was built by a good builder but I don't want to say anything because it may be, and probably is, any number of things not related to anything they did.

It could be as simple as it wants to be broken in a bit and / or, I am expecting too much out of it.

As to headspace measurement, I have not checked it but, I don't suspect it to be out of whack considering the reputation of the builder. If I can't figure it out in the next week or so, I will look more closely into that.

I went through it again today looking for anything obvious and the only thing I found were the action screws weren't as tight as I have seen people say they should be. I torqued them to 70 lb/in when i put it back together.

 

[tmwinds]

How does it shoot without the tuner?

 

[cavedweller60]

How does it shoot without the tuner?

THAT, is something I haven't tried yet. I will try it next time I go. Thanks for asking.

 

[TRSR8]

Couple thoughts then I’m out. First, I see you’re in Maine. Personally I’d wait a bit until you hit solid 50’s, Second, and this requires some trust, set the tuner at 200 and leave it there for the time being as a temporary step. You’d be surprised how many good smiths send them out the door right around that number. Lastly, 70iin/lb is WAY too much, most are 30-40, I’ve use 30 in/lb for years for 10lb and sporter rifles…..plenty for a pillar bedded setup, you want to go nuts go to 40 but I’ve used this for 25 years and guns show zero changes

 

[Rwfish]

If your strikes are consistent and all look like these pics I don’t think that is your problem. As others have said, you could Shave your spring length back a little if you think it may be striking too hard. What is your front rest set up? Any chance your getting some stock bounce? What stock and how does the bed look? As you said, there are allot of factors to look at….

 

[cavedweller60]

Couple thoughts then I’m out. First, I see you’re in Maine. Personally I’d wait a bit until you hit solid 50’s, Second, and this requires some trust, set the tuner at 200 and leave it there for the time being as a temporary step. You’d be surprised how many good smiths send them out the door right around that number. Lastly, 70iin/lb is WAY too much, most are 30-40, I’ve use 30 in/lb for years for 10lb and sporter rifles…..plenty for a pillar bedded setup, you want to go nuts go to 40 but I’ve used this for 25 years and guns show zero changes

If I wait til it hits the 50s it will be May...lol. I found an old post on the Stiller actions facebook page, https://www.facebook.com/permalink.php/?story_fbid=543676135812894&id=239775912869586, that says 45-65 but, I just realized it doesn't specify if they are speaking about a CF or RF action. It popped up in my search for "2500X action screw torque". I had it in my mind that it said 45-75 lb/in so I set it to 70. I will loosen and re-tighten properly. Thanks for your input though, I appreciate it.