F T/R Competition Reducing lock time....?

[BigtimeAub]

Lock time is the time between the break of the trigger and the striking of the primer by the firing pin, correct?

So, since this time is variable, and adjustable, would I be correct in saying that an F T/R shooter would benefit this more than a Benchrest shooter because the F T/R shooter has the rifle in a position that allows for movement, thus shortening the lock time would minimize the effect of the distance moved in the POA and POI from the moment the trigger breaks, where as the Benchrest shooter uses a fixed and stable platform thus negating any benefit gained from reducing said lock time? (Wow, that made my head hurt just typing that!)

If you could follow that tragedy of question, does that sound right? Also, would a beginner stand to gain more from upgrading components that would reduce lock time, since they have more room for improvement? Or would there still be so much error in a beginners shooting that any gains made would go virtually unnoticed?

If the answer is the latter, disregard this next question. If the answer is the prior, what combination of trigger/bolt components would need to be replaced/upgraded to create the biggest gains?

 

[Al_Ski]

Re: Reducing lock time....?

Where do you get the idea that benchrest rifles don't move?

 

[BigtimeAub]

Re: Reducing lock time....?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Al_Ski</div><div class="ubbcode-body">Where do you get the idea that benchrest rifles don't move? </div></div>I'm not totally certain that they don't move at all, but I would imagine with the type of rests that they are on, the movement of the barrel would be much less than that of an F T/R rifle. I'm just merely guessing, but in benchrest, other than your shoulder, the only point of contact would be your trigger finger and the entire weight of the rifle is being held up by the front and rear rests. For a visualization, a benchrest rifle could essentially be left in place without moving the cross hairs from the target. In contrast, the same cannot be said about an F T/R rifle on a bipod with just a rear bag.

I'm not trying to assert anything as fact. I'm simply asking a question predicated on my limited knowledge of the subject. If I'm wrong, please correct me. If you have something to add, please do. If not, thanks anyway.

 

[clmayfield]

Re: Reducing lock time....?

Lock time is more important the less stable your position is. For off-hand, it is more critical than accuracy because you are trying to break the trigger right when your sights align up with the target. If you think about stability from least stable to most stable, you have off-hand, seated, prone (slung up), prone (bipod), bench.

Benchrest and F-class both employ very stable positions, so I think increasing lock-time will have minimal impact. If you shoot at the bottom of your respiratory pause, the reticle should hang on the target with no movement... so reduced lock time will not accomplish anything.

Across the course guys focus on lock time because they shoot off-hand and in the seated positions.

Will lock time matter more to F-class than benchrest? Marginally, but across the course guys call F-class belly benchrest for a reason.

 

[BigtimeAub]

Re: Reducing lock time....?

That makes a lot of sense. Thanks!

 

[Zilla]

Re: Reducing lock time....?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Carter Mayfield</div><div class="ubbcode-body"> Marginally, but across the course guys call F-class belly benchrest for a reason. </div></div>


Because they don't know what they are talking about.

 

[memilanuk]

Re: Reducing lock time....?

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Across the course guys focus on lock time because they shoot off-hand and in the seated positions.</div></div>

Also because many of them shoot gas guns... most of which have lock times that can be measured with a freakin' sun dial as compared to most bolt action rifles.

If you're shooting F-class with a bolt gun, don't worry about it.

 

[XTR]

Re: Reducing lock time....?

I looked a little bit when I replaced the J lock shroud and firing pin on the 308 that I hunt with. I recall reading somewhere that R700 actions are very good in the lock time department. About the only thing you can do to speed it is a lighter firing pin and/or a stronger spring. Though a lighter pin may cause light strikes and misfires.

 

[Denys]

Re: Reducing lock time....?

I think it helps to judge this issue when you understand the numbers behind the qualitative comments; long, short, etc.

In an AR-15, the winningest rifle in XTC competition, the lock time of the standard trigger is 12 milliseconds. Bill Geissele addressed this issue with his High Speed trigger, which by design brought the lock time down to about 8ms.

A normal bolt action rifle will have a lock time of about 4 milliseconds, and using "exotic" materials and stronger springs this can be brought down to 3 or maybe two milliseconds.

As you can see there is a huge difference in lock times depending on the configuration of the trigger and spending money and effort to improve lock times on a bolt action rifle is probably not worthwhile, certainly not anywhere near what it is with an AR.

 

[pjparker]

Re: Reducing lock time....?

Denys and Dgosnell both have my respect for their capabilities and knowledge and I submit that faster locktime is better, no matter what you shoot...Faster is Better...no contest.

Paul

 

[Denys]

Re: Reducing lock time....?

Hi Paul. I don't disagree with you at all, however going from 12 to 8 is one thing, going from 4 to 3 is another even though they are both a 25% reduction.

In offhand position, removing 4 millisecond does make a difference on target, because you are always moving. In prone position, especially in something like F-Class, removing 1 millisecond is probably not as perceptible on the target.

 

[xs hedspace]

Re: Reducing lock time....?

What about the Holland striker kits for the Rem. Anybody see a real increase in accuracy from the better spring fit and shroud??

 

[Al_Ski]

Re: Reducing lock time....?

Lock time isn't as critical when compared to what happens after the primer is lit and until the bullet actually leaves the barrel. Consistency in follow through is what matters most.

 

[pjparker]

Re: Reducing lock time....?

Hey, Denys - leave it to you to put numbers to it, but you are, of course, correct. There is a point of diminishing returns, and in custom actions the issue has already been addressed by the maker, so no spring kit/magic metal pin will make the lock time quicker than they come out of the box.

Al_Ski - you have a valid point. Lock time and follow through are individual components to the overall accumulation of events that must take place for a shot to be consistently on target. I will leave prioritizing the order to others.

Paul

 

[Denys]

Re: Reducing lock time....?

Paul, I know you are going to be absolutely schocked to read this, but sometimes people try to buy accuracy using gadgets as opposed to developing their skills through practice and education. What Al_Ski said is correct, it would behoove the shooter more to learn proper follow through technique rather than shave a millisecond in lock time.

On the other hand, boys do love their toys.

 

[SNAFU_]

Re: Reducing lock time....?

if you can still see the carpet in your house....you don't have enough toys yet

 

[scotharr]

Re: Reducing lock time....?

F-class uses front and rear rests. Given the uber-stable position, lock-time is pretty low down the list of things to worry about. As mentioned, bolt rifles have good lock times already and lots of effort will only marginally improve on it. This is another subject that can be shelved....unless you like wasting your time. Lock-time is a discussion for XTC shooters to discuss...not too important for bolt gun F-classers.

On anothernote, while I certainly agree that better is better, better is not better if it reduces ignition quality. There are quite a few smart folks that believe light firing pins in bolt actions reduce ignition quality.

 

[Lukas Koukal]

Re: Reducing lock time....?

On the same note, I´ve posted a tech Q in the gunsmithing section a few days ago. This comes from the CG Jackson trigger assembly & set-up manual:

I believe their aim is just that - once the sear is disengaged, the bewelled edge of the cocking pin slides off and gets up to speed faster, therefore possibly reducing locking time. The trigger was originally developped for competition use.

I´d appreciate any dissent on it, since I´d like to understand the technical aspects of this bit a little more thoroughly.

 

[Greg Langelius *]

Re: Reducing lock time....?

Logically, your idea is sound.

In practice, I seriously doubt that replacing a fire control system to improve lock time is going to have a significant bearing on your rifle's observed performance.

Simply put, neither application you mention is heavily dependent on lock time. Since both applications work from a seriously stable support, significant motion which would require faster lock time is simply not present.

Spend your money if you want, but I'd not be surprised if you have significant difficulty seeing any real difference when you're done.

Greg