So ive been running the new NDZ SBR for about a week and I have to say I'm slightly disappointed. While the craftsmanship and quality is top notch, it just doesn't function very well. Because of the added weight on the bolt release paddle, the bolt won't lock back after my last round which causes me to dry fire the weapon, which is never good for an AR. It also causes the bolt to slam home with the slightest movement of the gun, mag reload (not a big deal for this one), placing the gun down etc. I don't want to give up on it, but I do not want to count shots fired every mag to avoid a dry fire when my bolt doesn't lock open. Please share your findings and any reviews you may have. Thanks all and happy fourth!

Why is dry firing never good for an AR? I understand why it can be detrimental to a .22, but an AR?

And unless the firing pin is long enough to hit the edge of the chamber, it doesn't hurt .22s, either.

Dry-firing is an integral part of carbine training and recommended by many top trainers. It will not harm a center-fire AR.

Exactly.

I was told by a gunsmith that dry firing an AR is no good for it at all. It's not analogous to dry firing a pistol. Not sure of the reasons why as I'm not a smith, but until someone (aka a smith) can weigh in as to why it's not detrimental, I have to go on the advice of the guy I spoke to....

If you're worried about it, get some .223 REM A-Zoom snap caps.

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-John

It won't hurt and AR. If your AR is built so fragile that it'll break it if you dry fire it, get another brand.

If your rifle fails to lock back on empty and you dry fire it? Sorta like what can happen and what you say does happen? Even repeated dry firing of an AR won't damage anything inside it. There is nothing TO damage. The pin will hit empty space. And the bolt face will be strong enough to survive getting hit by the firing pin. If it wasn't it would shatter when you fired a round.

This isnt' to say firing pins won't break, I've had them break even when used with ammo, but that rifle was (IIRC) 35 years old. (AR-15 SP1, old school slab side AR-15). anything made by man can fail.

But they won't be damaged by dry firing.

And that's why I said it _can_ be detrimental to .22's. I've had some that had pins that did hit the front, and through repeated dry firing have been peened flat/curled. I haven't experienced it on a 15/22 yet though.....

KBK

i think the original point here, is anyone else having problems with their sbr lever? i installed it but havent used it yet.

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od: xd9 3"&4", 15-22, 1911 .22

Thanks w0ady


Zack
Using Tapatalk

Hey PMB,
same thing happened to me after I installed the SBR on my rifle. Functions as expected manually with or without mag, but last round hold open will no longer work even with hyper velocity ammo. SBR is not catching/rubbing on receiver and my trigger finger is well away from the release lever.

i think id be more worried about chambering a round when i would rather not. too bad ndz isnt on the forum to discuss this. once we get more feedback, maybe we can point them this way.

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od: xd9 3"&4", 15-22, 1911 .22

Not all gunsmiths are as smart, or as knowledgeable, as they think they are. Many just pass along what someone else told them with no thought whether or not it is accurate. Or what they read somewhere on the I'net.

Page 14 of M&P 15-22 manual states:
Caution: Never dry-fire the rifle as damage to the firearm could result.

Here's the skinny about dry firing an AR:

The real problem is dry firing it with the upper and lower receiver separated. If done like this, the hammer (usually steel) strikes the lower (usually aluminum) and the hammer eventually wins.

When an AR is fully assembled, the hammer (steel) hits the firing pin (steel) so no damage can occur.

Now, with regards to the M&P 15-22 and the manual itself, maybe S&W uses an aluminum firing pin and since it uses a standard AR15 fire control group (steel) it can cause damage.

With that out of the way, pmbspyder, if you're having lock back problems with the NDZ SBR then I recommend you remove it and try again. If it fixes your problem then I suggest you make a claim with NDZ for a replacement or a refund.

Not supportable by any documented testing. Many manufacturers state that as a CYA insurance ploy. Same deal with firing anything but factory ammo. Bean counter statement.

As to dry-firing, go check any of the hundreds of thousands of M16A2s\A4s that Basic trainees have been using and abusing for a few decades - where dry-firing is an integral part of the POI.

i'v just got mine installed and noticed that the bolt would slam closed with any shaking or even with turning the gun upside down... to fix that issue iv shimmed the bolt release forward to remove some of the SBR's play.. i also removed all lube from where the catch and bolt meet. keep in mind i have not yet fired the gun with the lever installed yet but figure this would help a little... my next step is to cut the bolt catch spring to remove some pressure as the added weight of the lever is causing LRHO issues as id assumed would happen.. Juv's lever was having the same issue in its early stages with some of his mags.

I think the problems mine had in the first stage was a combination of two different things. The first was weight, so I skeletonized the arm and made the attach point as light as possible. But I learned that out of the mags I had the one that would not hold open after the last Roundhead a shorter bolt catch engaging rod, maybe .035 or .040 shorter than the others.
As far as releasing the bolt with slight bumps or movements I haven't seen that. I've had the 3rd revision on my gun for a long time and it has not done that yet.

Maybe it is just too heavy for the mag spring to hold up.

Yes, dry-firing an AR lower with the upper removed is a Very Bad Thing©.

True, but that is very different from dry firing complete weapons.

Got it, maybe he was talking about dry firing it while it was separated... Thank for the info guys, I always enjoy learning new stuff.

As far as the SBR, I'm going to call NDZ an see what's up. I'll keep you all posted...

You can dry-fire an AR lower with the upper removed --- as long as you have one of your least important fingers positioned so as to keep the hammer from hitting the reciever; while having another finger on the hammer while you press the trigger.

So I just got off the phone with Paul at NDZ. Great guy and more than stands behind his product. Apparently he reads the forums and tried to join to reply but admin hasn't confirmed him yet. Anyway, he's aware of the problem and thinks it could be a clearance issue that may be occurring (we're talking like tiny measurements). They are addressing it on the ones they're shipping out now and he's hoping that will clear up the problem if anyone else is having it. He also said that they will do whatever they can to bring this product to market, meaning that they're in it for the long haul no matter the fix.

I'm going to send mine back and he will mill a tiny bit of aluminum to clear the contact point. It weighs 8grams just like the bad lever so he doesn't think it's a weight issue.

Lastly, at Paul's request, for those of you who have ran the SBR already, please shoot NDZ an email describing the problem so thy can see what kind of scale the malfunction is happening on. He's a stand up guy and will do right by you.

Hope this helps for anyone else having the issue!

I don't know what company NDZ is. As for SBR --- I'm assuming that you mean short barreled rifle? If that is the case --- you might need to change your buffer; and maybe the buffer spring.

It is a battery assist lever, same concept as the Magpul BAD. The 15-22 lower receiver is physically different than an AR15 lower, and NDZ has made their version of the BAD lever and call it Speed Bolt Release.

cool to see ndz standing behind their product. ill be sure to shoot them an email if mine has the same issues.

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od: xd9 3"&4", 15-22, 1911 .22

If its making contact with the lower anywhere that could do it, make it not fully actuate and fall off the bolt face easer. Gotta make sure the only place it touches is the paddle area, it is good to see them fixing/replacing the defective ones.

Now I'm curious about mine. I haven't had a chance to hit the range since installing it so I don't know if mine has the problem described. Will do my best to get to the range tomorrow and find out.

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USN 1992-2002
ET1 (SW/AW)

well went to the range today and im having the same problem - it rarely locks open and when it does, the smallest movement such as touching the trigger causes it to slam closed. not a huge deal but looks like i will be emailing ndz for some follow-up.

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od: xd9 3"&4", 15-22, 1911 .22

I'll be going to the range tomorrow as well to test out my SBR. I guess I should expect mine to have the same problems as well =(

Is the sbr supposed to be making contact with the trigger guard when the bolt is locked back? I just think after time it may wear down the polymer.

sent them an email last night but it was after working hours so i will let you know next week when i hear back.

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od: xd9 3"&4", 15-22, 1911 .22

I don't think it should be touching anything when it goes to lock back. That's the problem I bet, it's not fully engaging the bolt face so any little bump or movement could let it slip off.

That was the fun part of making one that worked was figuring out the correct placement of when the arm has to bend to be close to the lower but not so close that when the arm moves it hits.

Do you guys think the type of mags (25rd long, 10rd long, or 10rd short) being used make a difference?

It shouldn't. Like I said before, out of my mags the only one that had problems was the one with a slightly shorter post on the follower.

That being said I don't have 10 round mags, but the other fella I had test did, and it worked for him.

If the arm is touching anything other than the bolt catch release where it attaches that's going to be a problem. The spring in the mag has to overcome the weight of the added arm, and the spring in the bolt catch release, anything else stopping it is probably too much.

Range report from my gun. My SBR ran 100% flawlessly through ~50 rounds of CCI Blazers and ~10 mag changes. The bolt locked back every time my mags were empty. The bolt also did not accidentally close.

I used one 10rd long mag that came with my gun and two 10rd short mags that I bought off 44mag.

I don't know if it matters but I have a Mass compliant rifle with the JP yellow spring kit installed.

Really??? You are going to modify your stock rifle to make a $36.00 accessory that apparently is not ready for the market yet work? This thread amazed me. Cutting springs and adding shims just to make a tactically cool but non functional accessory work is over the top in my humble opinion. Inadvertent bolt releases…. No bolt stay open….All for an item that lets you keep your finger inside the trigger guard during magazine changes….sounds downright dangerous to me.
I am going out to my garage….if I can make something COOL for my rifle someone here will buy it

I know, right?

Funny thing, I haven't had any problems changing magazines and using the factory bolt release to close the bolt. No last-round hold-open problems, no accidental bolt releases, and I haven't sprained my wrist by using my left hand to hit the bog-standard bolt release that every AR-15 pattern rifle for ~50 years has had.
I must be doing something wrong.

im not sure if you meant to come across so judgmental about the entire thread or just one person's reply. everyone else seems to be just testing theirs out or contacting NDZ for follow-up.

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od: xd9 3"&4", 15-22, 1911 .22

so i guess you have a 100% stock rifle and have never added anything to improve it?

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od: xd9 3"&4", 15-22, 1911 .22

I don’t think I need to apologize for what I said but maybe how I said it. The post did have attitude and a harsh tone. I am self employed and like to see all companies do well, especially small ones. I am not familiar with NDZ but reading this thread I got the impression the product is clearly not market ready. Their web site says it is. It seems to me this is another case of someone rushing a product to market before it is completely functional. An all too common occurrence these days in many product categories. If I am going to be a beta tester that is fine, as long as I KNOW I am beta testing! That’s all I ask.

In this case we are talking about a rifle accessory. I stand behind my comment and OPINION that any accessory that causes my bolt to malfunction WHILE my finger is still inside the trigger guard is dangerous.

That’s my .2 cents worth. That is all it is. But my bolt stays open after the last shot EVERY time and my mags release EVERY time.

i am not 100% happy with NDZ releasing a product that isnt ready but it does make me feel better that they are standing behind it and providing the follow-up needed. in case you forget, even the major gun companies have all released firearms with issues but the ones that are successful are the ones that followed up on it.

is it a flaw that the bolt doesnt lock open on an EMPTY mag? sure. is it dangerous? not necessarily. i would be a lot more upset if it affected the performance of the rifle while firing but it doesnt. yes its an accessory but so is just about everything that people add to their rifles. it works just fine from the factory but we all feel the need to personalize.

i agree that i would never modify my rifle's function for an accessory but ill give NDZ a chance to correct their flaw. if not, then i expect my $ back and ill move on.

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od: xd9 3"&4", 15-22, 1911 .22

Back to the original question. I too installed the SBR, got to shoot some rounds, but did not do a full test. I'll be doing that this Friday the 13th. I did not have any failures, the bolt latched up, SBR did what is was suppose to do, speed up re-loads, help bolt up on rapid bolt checks and held the bolt back on the last shot with the SBR attached. The added weight of the SBR did not affect the bolt latch function at this point. I will update this post after 7-13... Good luck..

For ones who are having that issue, make sure the bolt latch is clean and lightly oiled so it is free to move from the magazine insertion as well as the bolt latch itself. Maybe added weight and dirt is causing some to have no latch up on the last round. Again Good Luck.

Well said. I made this thread as a litmus test for a new product, not to debate the merits of aftermarket add-ons. To each his own is what I say.

Gentlemen, wooo... This product is pretty simple in design, it is not rocket science. This product does work, it works on my M&P 15/22. Before we throw anyone under the bus, each and every weapon is different and we have no way of know how many rounds in one person's weapon from anothers NEW weapon. If the weight off-sets the bolt latch, then EVERYONE that installs it may have the same problem, that is not the case here. I've communicated with Paul and I am going to run the SBR into the ground, so to speak, this 13th with some solid testing on a range. I'll update accordingly.. NDZ makes some great products and based on my several purchases and emails with Paul, I believe he is very concerned about hearing issues on the SBR. And PS, NO I don't work for NDZ, I'm just a customer... Hang on guys, I'll post the results in week...

Yes, I agree, it is simple in form and function. The problem here seems to be one of clearance. In talking to Paul it seems to be thousanths of an inch. This means that any slight variance in materials in the gun, paddle, spring, etc, could cause different guns to operate with different results. NDZ wants to put a product out that can work with all 15-22s, therefor I'm sure they want to address the issue. It's been tested by several with varying results here. The definitive conclusion is that there is not enough clearance and it is defective on some. If it works on yours that's awesome, but it doesn't mean the product isn't defective. Like I said in earlier posts, Paul seems like a stand up guy and the company has been sterling so far. This is not an indictment of NDZ, just honest consumer feedback.

I'm not convinced that losing last round hold open and repeated accidental bolt releases are improvements.

Please post the types of magazines you are using and what results you get. I'm just curious because the SBR works fine with my short and long 10rd mags.

It appears that the mag release paddle has to be removed for the SBR to be installed. Is this correct?

I am using the 10 round shorty, 10/30 round long mag & the 10 round long mag. My SBR works on all of my mags. NO the bolt latch does NOT have to be removed, it can be installed on the rifle as is.

It may be the way some installed it. I dis-assembled mine again and I think I know what may be going on. NDZ made the SBR cutout aluminum upper to fit the thumb pad of the latch, it is very tight I've notice. You have to fit the SBR and use a pliers (tape the tip so you don't mark the SBR) smash the SBR and paddle with the pliers together around all the edges, then install the screw and back plate. You may have the SBR crooked and angle in to much if it's not completly pressed into the latch pad.. and NO the SBR is not touching the receiver in the LATCHed up mode. Look at PHOTOS:
SBR position UN-latched:


SBR position LATCHED: