Big bluff

I have been making large bluffs quite frequently in 100NL. If I actually get the correct read, they work 85% of the time. How often do you guys make bluffs like these? Usually I bluff a little right when I sit down, then sit back and let them pay me off. It's been working great. Yeah, it's a little crazy, but it's been working.

PokerStars Game #2200534699: Hold'em No Limit ($0.50/$1.00) - 2005/07/27 - 15:55:34 (ET)
Table 'Sorga' Seat #5 is the button
Seat 1: slidr0n2 ($85.25 in chips)
Seat 2: garompon ($141.80 in chips)
Seat 3: Snuskas ($126.30 in chips)
Seat 4: skindog ($50.85 in chips)
Seat 5: GoinBak2Cali ($124.90 in chips)
slidr0n2: posts small blind $0.50
garompon: posts big blind $1
*** HOLE CARDS ***
Dealt to GoinBak2Cali [6h Qs]
Snuskas: folds
Hustl U leaves the table
PokerAstro joins the table at seat #6
skindog has timed out
skindog: folds
skindog is sitting out
GoinBak2Cali: raises $3 to $4
slidr0n2: calls $3.50
garompon: folds
*** FLOP *** [4c 7c 4s]
skindog has returned
slidr0n2: bets $5
GoinBak2Cali: raises $5 to $10
slidr0n2: calls $5
*** TURN *** [4c 7c 4s] [2d]
slidr0n2: bets $9
GoinBak2Cali: raises $18 to $27
slidr0n2: calls $18
*** RIVER *** [4c 7c 4s 2d] [3h]
slidr0n2: checks
GoinBak2Cali: bets $83.90 and is all-in
slidr0n2: folds
GoinBak2Cali collected $81 from pot
GoinBak2Cali: shows [6h Qs] (a pair of Fours)
*** SUMMARY ***
Total pot $83 | Rake $2
Board [4c 7c 4s 2d 3h]
Seat 1: slidr0n2 (small blind) folded on the River
Seat 2: garompon (big blind) folded before Flop
Seat 3: Snuskas folded before Flop (didn't bet)
Seat 4: skindog folded before Flop (didn't bet)
Seat 5: GoinBak2Cali (button) collected ($81)

good bet on the river, i find anyone who flat calls both streets and checks on the river was clearly on a draw and you can bluff him out