Bolt Lift Effort

[MarkInFolsom]

I'm curious about the bolt lift effort of the various brands of bolt action rifles.

I have a Savage 110 action, Kleinguenther Titan II action, and a custom gun based on a Mauser action.

I estimate the Savage action at about 6 lbs, the titan II at 10 lbs, and the Mauser at 8 lbs.

I've always heard the Savage sucks at cocking, but The Kleinguenther, I thought, was supposedly one of Germany's finest. But it has a stiff bolt lift and about a 1/4" "push" on bolt close. The Mauser is just "stiff".

My question is, how is the bolt lift effort on a Remington 700? Or a higher end action like Surgeon, Borden, Stiller, or others? Is it smoother? Just as much effort as the above? Or less? Or am I just expecting too much?

Thanks.

[TMB 1]

Grandpa said " Don't believe anything you hear and only half of what you see"

[ar15barrels]

My question is, how is the bolt lift effort on a Remington 700? Or a higher end action like Surgeon, Borden, Stiller, or others? Is it smoother? Just as much effort as the above? Or less? Or am I just expecting too much?

The cocking effort is a function of the amount of cocking piece travel, the amount of striker tension and the angle of bolt lift.
Longer striker travel will increase the bolt lift feel.
Heavier spring tension will increase the bolt lift feel.
Shorter unlocking angle will increase the bolt lift feel.
2 lug actions generally have 75-90 degree bolt lifts.
3 lug actions generally have 60 degree bolt lifts.
Shorter bolt handle lengths will increase the bolt lift feel.
For the smoothest bolt lift, look for a 90 degree lift with a short striker travel, an extended bolt knob and a lighter striker spring.

Savages have a long striker travel because of the way the bolt body interacts with the striker that sits in the side rail of the receiver.
Savages also have more moving parts in the striker so they probably need more spring tension to get that extra weight moving reliablly.
700's have some of the shortest firing pin travels of the commonly available (non target rifle) actions.
The other actions you mentioned such as Surgeon, Borden and Stiller all use the 700 design.
Any of them can usually be improved with some polishing and adjusting of the clearances to optimize them.
Proper lubrication is also important.
Dry parts will be much harder to move than properly lubed parts.
Oversized bolt knobs are generally longer than the original knob so they reduce the feel of the bolt lift.

[LynnJr]

Bolt lift is affected by several things.
Two lug actions naturally have only 2 lugs and they are 180 degrees apart and have 90 degrees of swing from closed to open so the cocking ramp is relatively long.
Three lug actions naturally have 3 lugs each of which is 120 degrees apart and have 60 degrees of travel from fully open to fully closed. The opening ramp on a 3 lug action is typically 1/3 shorter so bolt lift takes more effort.
You are doing the same amount of work in a much shorter distance so the effort is increased.

The next issue is the firing pin spring pressure.
Typical firing pin springs run from 16-18 pounds on a Borden Benchrest action with 2 lugs.
On a Remington 700 with 2 lugs you can use a 28 pound spring but in doing so you increase the bolt lift effort quite a bit.
BAT Machine introduced a line of 3 lug actions several years back and the first thing that came up was bolt lift effort. On Benchrest rifles if you have heavy bolt opening the gun will rock in the bags causing the sand to mound up in the middle ruining accuracy.
Bruce Thom the owner at BAT came up with a rollerized cocking piece to make the lift on the 3 lug actions less than that of a typical 2 lug action.
Naturally everyone with a 2 lug BAT action added the rollerized cocking piece and the effort is very light on those actions.

Long bolt handles help as they have the added leverage.
The tolerances on the bolt to action fit make a small contribution.
The Stiller actions are about the same as factory Remingtons with a 22-24 pound spring.
I don't use Surgeon actions due to the one piece bolts so can't comment on them but the BAT 2 lug with the roller cocking piece and a 18 pound firing pin spring seems effortless compared to most other actions.

[MarkInFolsom]

Thanks guys, great explanations.


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[smalltime]

My Howa feels like 20lbs. Pretty much have to hold the rifle down while operating the bolt.

[postal]

It also come down to 'timing'....

Spreading the effort of the cocking piece evenly across the bolt lift.

Savages arent bad for cocking effort, but Fred Moreo at SSS offers a 'timing service'. I played with a savage he worked on, and it was a very noticable difference.

[JMP]

You can also get your bolt sticky if your pressure is too high. Cheaper actions generally struggle more with high pressure.

[23 Blast]

My Howa feels like 20lbs. Pretty much have to hold the rifle down while operating the bolt.

Really? Mine is extremely smooth. However, I do have an extended bolt handle, and the previous owner polished the bolt. The only other action I'd handled that was as smooth was an old VZ-24 Czech Mauser from Big 5 that had probably had a million rounds through it.

[Fjold]

Savages also have the cocking cam cut wrong by the factory. They use a straight end mill and cut a series of angles to make an arc. Sharpshooter Supply uses a hollow ground cutter to make a smooth helical cut on the cam when they rework an action.

Savage also uses a heavy spring to decrease the lock time.

[smalltime]

Really? Mine is extremely smooth. However, I do have an extended bolt handle, and the previous owner polished the bolt. The only other action I'd handled that was as smooth was an old VZ-24 Czech Mauser from Big 5 that had probably had a million rounds through it.

I was curious so I picked up a fish scale and it says I caught an 18 lber! Trigger shows 3lbs, I like that part.

[23 Blast]

I was curious so I picked up a fish scale and it says I caught an 18 lber! Trigger shows 3lbs, I like that part.

Yes, the trigger on mine is very light and crisp.

[milotrain]

I'm digging this back up from the grave because I've been trying to do a bit of research on the cocking-piece sear handoff in the 700.

I'm assuming that it is desirable to have the cocking-piece catch the sear far enough back that it maintains enough spring pressure for reliable ignition, but far enough forward that you are not getting excessive lock time, heavier bolt lift, or an unsafe handoff jump. Looking at PTGs website they sell a cocking piece that has 30 thou taken off the sear engagement surface. Is the management of this surface the extent of manipulating handoff, and in normal circumstances can I assume 30thou is the max amount of removal?

[ar15barrels]

I'm digging this back up from the grave because I've been trying to do a bit of research on the cocking-piece sear handoff in the 700.

I'm assuming that it is desirable to have the cocking-piece catch the sear far enough back that it maintains enough spring pressure for reliable ignition, but far enough forward that you are not getting excessive lock time, heavier bolt lift, or an unsafe handoff jump. Looking at PTGs website they sell a cocking piece that has 30 thou taken off the sear engagement surface. Is the management of this surface the extent of manipulating handoff, and in normal circumstances can I assume 30thou is the max amount of removal?

When I do my bolt tuning work, I am working on the hand-off from the bolt body to the sear on the trigger unit.
Look at the handoff AFTER the cocking piece comes out of the detent and see how much extra striker travel you have as the lugs fully engage the action.
Remove that excess striker travel from the angled face of the cocking piece where it contacts the sear.
Don't take off any extra though or you end up with a problem where the striker won't re-cock without moving the bolt slightly to the rear to pick up the cocking piece.

[milotrain]

Don't take off any extra though or you end up with a problem where the striker won't re-cock without moving the bolt slightly to the rear to pick up the cocking piece.

I've read that before, and I'm assuming that's basically what happened with the guy who installed a Timney trigger with light strikes. I'm just having trouble visualizing it as it seems like more material you remove from the sear engagement surface on the cocking piece the easier it would be to pick up the trigger sear.